ClassWriter

java.lang.Object
- org.springframework.asm.ClassVisitor
- - org.springframework.asm.ClassWriter

```
public class ClassWriter
extends ClassVisitor
```
A ClassVisitor that generates classes in bytecode form. More precisely this visitor generates a byte array conforming to the Java class file format. It can be used alone, to generate a Java class "from scratch", or with one or more ClassReader and adapter class visitor to generate a modified class from one or more existing Java classes.

Author:

Eric Bruneton

Field Summary

Fields
Modifier and Type	Field and Description
`(package private) static int`	`ACC_SYNTHETIC_ATTRIBUTE` Pseudo access flag to distinguish between the synthetic attribute and the synthetic access flag.
`private int`	`access` The access flags of this class.
`private AnnotationWriter`	`anns` The runtime visible annotations of this class.
`private Attribute`	`attrs` The non standard attributes of this class.
`(package private) ByteVector`	`bootstrapMethods` The BootstrapMethods attribute.
`(package private) int`	`bootstrapMethodsCount` The number of entries in the BootstrapMethods attribute.
`(package private) static int`	`BSM` The type of BootstrapMethods items.
`(package private) static int`	`CLASS` The type of CONSTANT_Class constant pool items.
`static int`	`COMPUTE_FRAMES` Flag to automatically compute the stack map frames of methods from scratch.
`static int`	`COMPUTE_MAXS` Flag to automatically compute the maximum stack size and the maximum number of local variables of methods.
`private boolean`	`computeFrames` `true` if the stack map frames must be recomputed from scratch.
`private boolean`	`computeMaxs` `true` if the maximum stack size and number of local variables must be automatically computed.
`(package private) ClassReader`	`cr` The class reader from which this class writer was constructed, if any.
`(package private) static int`	`DOUBLE` The type of CONSTANT_Double constant pool items.
`private int`	`enclosingMethod` The constant pool item that contains the name and descriptor of the enclosing method of this class.
`private int`	`enclosingMethodOwner` The constant pool item that contains the name of the enclosing class of this class.
`(package private) static int`	`FIELD` The type of CONSTANT_Fieldref constant pool items.
`(package private) static int`	`FIELDORMETH_INSN` The type of field and method invocations instructions.
`(package private) FieldWriter`	`firstField` The fields of this class.
`(package private) MethodWriter`	`firstMethod` The methods of this class.
`(package private) static int`	`FLOAT` The type of CONSTANT_Float constant pool items.
`(package private) static int`	`HANDLE` The type of CONSTANT_MethodHandle constant pool items.
`(package private) static int`	`HANDLE_BASE` The base value for all CONSTANT_MethodHandle constant pool items.
`private AnnotationWriter`	`ianns` The runtime invisible annotations of this class.
`(package private) static int`	`IINC_INSN` The type of the IINC instruction.
`(package private) static int`	`IMETH` The type of CONSTANT_InterfaceMethodref constant pool items.
`(package private) static int`	`IMPLVAR_INSN` The type of instructions with an implicit local variable index argument.
`(package private) int`	`index` Index of the next item to be added in the constant pool.
`(package private) static int`	`INDY` The type of CONSTANT_InvokeDynamic constant pool items.
`(package private) static int`	`INDYMETH_INSN` The type of the INVOKEDYNAMIC instruction.
`private ByteVector`	`innerClasses` The InnerClasses attribute.
`private int`	`innerClassesCount` The number of entries in the InnerClasses attribute.
`(package private) static int`	`INT` The type of CONSTANT_Integer constant pool items.
`private int`	`interfaceCount` Number of interfaces implemented or extended by this class or interface.
`private int[]`	`interfaces` The interfaces implemented or extended by this class or interface.
`(package private) boolean`	`invalidFrames` `true` if the stack map tables of this class are invalid.
`private AnnotationWriter`	`itanns` The runtime invisible type annotations of this class.
`(package private) Item[]`	`items` The constant pool's hash table data.
`(package private) static int`	`ITFMETH_INSN` The type of the INVOKEINTERFACE/INVOKEDYNAMIC instruction.
`(package private) Item`	`key` A reusable key used to look for items in the `items` hash table.
`(package private) Item`	`key2` A reusable key used to look for items in the `items` hash table.
`(package private) Item`	`key3` A reusable key used to look for items in the `items` hash table.
`(package private) Item`	`key4` A reusable key used to look for items in the `items` hash table.
`(package private) static int`	`LABEL_INSN` The type of instructions with a 2 bytes bytecode offset label.
`(package private) static int`	`LABELW_INSN` The type of instructions with a 4 bytes bytecode offset label.
`(package private) FieldWriter`	`lastField` The fields of this class.
`(package private) MethodWriter`	`lastMethod` The methods of this class.
`(package private) static int`	`LDC_INSN` The type of the LDC instruction.
`(package private) static int`	`LDCW_INSN` The type of the LDC_W and LDC2_W instructions.
`(package private) static int`	`LONG` The type of CONSTANT_Long constant pool items.
`(package private) static int`	`LOOK_INSN` The type of the LOOKUPSWITCH instruction.
`(package private) static int`	`MANA_INSN` The type of the MULTIANEWARRAY instruction.
`(package private) static int`	`METH` The type of CONSTANT_Methodref constant pool items.
`(package private) static int`	`MTYPE` The type of CONSTANT_MethodType constant pool items.
`private int`	`name` The constant pool item that contains the internal name of this class.
`(package private) static int`	`NAME_TYPE` The type of CONSTANT_NameAndType constant pool items.
`(package private) static int`	`NOARG_INSN` The type of instructions without any argument.
`(package private) ByteVector`	`pool` The constant pool of this class.
`(package private) static int`	`SBYTE_INSN` The type of instructions with an signed byte argument.
`(package private) static int`	`SHORT_INSN` The type of instructions with an signed short argument.
`private int`	`signature` The constant pool item that contains the signature of this class.
`private ByteVector`	`sourceDebug` The SourceDebug attribute of this class.
`private int`	`sourceFile` The index of the constant pool item that contains the name of the source file from which this class was compiled.
`(package private) static int`	`STR` The type of CONSTANT_String constant pool items.
`private int`	`superName` The constant pool item that contains the internal name of the super class of this class.
`(package private) static int`	`TABL_INSN` The type of the TABLESWITCH instruction.
`private AnnotationWriter`	`tanns` The runtime visible type annotations of this class.
`(package private) java.lang.String`	`thisName` The internal name of this class.
`(package private) int`	`threshold` The threshold of the constant pool's hash table.
`(package private) static int`	`TO_ACC_SYNTHETIC` Factor to convert from ACC_SYNTHETIC_ATTRIBUTE to Opcode.ACC_SYNTHETIC.
`(package private) static byte[]`	`TYPE` The instruction types of all JVM opcodes.
`(package private) static int`	`TYPE_INSN` The type of instructions with a type descriptor argument.
`(package private) static int`	`TYPE_MERGED` Merged type Item stored in the ClassWriter `typeTable`, instead of the constant pool, in order to avoid clashes with normal constant pool items in the ClassWriter constant pool's hash table.
`(package private) static int`	`TYPE_NORMAL` Normal type Item stored in the ClassWriter `typeTable`, instead of the constant pool, in order to avoid clashes with normal constant pool items in the ClassWriter constant pool's hash table.
`(package private) static int`	`TYPE_UNINIT` Uninitialized type Item stored in the ClassWriter `typeTable`, instead of the constant pool, in order to avoid clashes with normal constant pool items in the ClassWriter constant pool's hash table.
`private short`	`typeCount` Number of elements in the `typeTable` array.
`(package private) Item[]`	`typeTable` A type table used to temporarily store internal names that will not necessarily be stored in the constant pool.
`(package private) static int`	`UTF8` The type of CONSTANT_Utf8 constant pool items.
`(package private) static int`	`VAR_INSN` The type of instructions with a local variable index argument.
`(package private) int`	`version` Minor and major version numbers of the class to be generated.
`(package private) static int`	`WIDE_INSN` The type of the WIDE instruction.

Fields inherited from class org.springframework.asm.ClassVisitor
api, cv

Constructor Summary

Constructors
Constructor and Description
`ClassWriter(ClassReader classReader, int flags)` Constructs a new `ClassWriter` object and enables optimizations for "mostly add" bytecode transformations.
`ClassWriter(int flags)` Constructs a new `ClassWriter` object.

Method Summary

All Methods Instance Methods Concrete Methods
Modifier and Type	Method and Description
`private Item`	`addType(Item item)` Adds the given Item to `typeTable`.
`(package private) int`	`addType(java.lang.String type)` Adds the given internal name to `typeTable` and returns its index.
`(package private) int`	`addUninitializedType(java.lang.String type, int offset)` Adds the given "uninitialized" type to `typeTable` and returns its index.
`private Item`	`get(Item key)` Returns the constant pool's hash table item which is equal to the given item.
`protected java.lang.String`	`getCommonSuperClass(java.lang.String type1, java.lang.String type2)` Returns the common super type of the two given types.
`(package private) int`	`getMergedType(int type1, int type2)` Returns the index of the common super type of the two given types.
`int`	`newClass(java.lang.String value)` Adds a class reference to the constant pool of the class being build.
`(package private) Item`	`newClassItem(java.lang.String value)` Adds a class reference to the constant pool of the class being build.
`int`	`newConst(java.lang.Object cst)` Adds a number or string constant to the constant pool of the class being build.
`(package private) Item`	`newConstItem(java.lang.Object cst)` Adds a number or string constant to the constant pool of the class being build.
`(package private) Item`	`newDouble(double value)` Adds a double to the constant pool of the class being build.
`int`	`newField(java.lang.String owner, java.lang.String name, java.lang.String desc)` Adds a field reference to the constant pool of the class being build.
`(package private) Item`	`newFieldItem(java.lang.String owner, java.lang.String name, java.lang.String desc)` Adds a field reference to the constant pool of the class being build.
`(package private) Item`	`newFloat(float value)` Adds a float to the constant pool of the class being build.
`int`	`newHandle(int tag, java.lang.String owner, java.lang.String name, java.lang.String desc)` Adds a handle to the constant pool of the class being build.
`(package private) Item`	`newHandleItem(int tag, java.lang.String owner, java.lang.String name, java.lang.String desc)` Adds a handle to the constant pool of the class being build.
`(package private) Item`	`newInteger(int value)` Adds an integer to the constant pool of the class being build.
`int`	`newInvokeDynamic(java.lang.String name, java.lang.String desc, Handle bsm, java.lang.Object... bsmArgs)` Adds an invokedynamic reference to the constant pool of the class being build.
`(package private) Item`	`newInvokeDynamicItem(java.lang.String name, java.lang.String desc, Handle bsm, java.lang.Object... bsmArgs)` Adds an invokedynamic reference to the constant pool of the class being build.
`(package private) Item`	`newLong(long value)` Adds a long to the constant pool of the class being build.
`int`	`newMethod(java.lang.String owner, java.lang.String name, java.lang.String desc, boolean itf)` Adds a method reference to the constant pool of the class being build.
`(package private) Item`	`newMethodItem(java.lang.String owner, java.lang.String name, java.lang.String desc, boolean itf)` Adds a method reference to the constant pool of the class being build.
`int`	`newMethodType(java.lang.String methodDesc)` Adds a method type reference to the constant pool of the class being build.
`(package private) Item`	`newMethodTypeItem(java.lang.String methodDesc)` Adds a method type reference to the constant pool of the class being build.
`int`	`newNameType(java.lang.String name, java.lang.String desc)` Adds a name and type to the constant pool of the class being build.
`(package private) Item`	`newNameTypeItem(java.lang.String name, java.lang.String desc)` Adds a name and type to the constant pool of the class being build.
`private Item`	`newString(java.lang.String value)` Adds a string to the constant pool of the class being build.
`int`	`newUTF8(java.lang.String value)` Adds an UTF8 string to the constant pool of the class being build.
`private void`	`put(Item i)` Puts the given item in the constant pool's hash table.
`private void`	`put112(int b1, int b2, int s)` Puts two bytes and one short into the constant pool.
`private void`	`put122(int b, int s1, int s2)` Puts one byte and two shorts into the constant pool.
`byte[]`	`toByteArray()` Returns the bytecode of the class that was build with this class writer.
`void`	`visit(int version, int access, java.lang.String name, java.lang.String signature, java.lang.String superName, java.lang.String[] interfaces)` Visits the header of the class.
`AnnotationVisitor`	`visitAnnotation(java.lang.String desc, boolean visible)` Visits an annotation of the class.
`void`	`visitAttribute(Attribute attr)` Visits a non standard attribute of the class.
`void`	`visitEnd()` Visits the end of the class.
`FieldVisitor`	`visitField(int access, java.lang.String name, java.lang.String desc, java.lang.String signature, java.lang.Object value)` Visits a field of the class.
`void`	`visitInnerClass(java.lang.String name, java.lang.String outerName, java.lang.String innerName, int access)` Visits information about an inner class.
`MethodVisitor`	`visitMethod(int access, java.lang.String name, java.lang.String desc, java.lang.String signature, java.lang.String[] exceptions)` Visits a method of the class.
`void`	`visitOuterClass(java.lang.String owner, java.lang.String name, java.lang.String desc)` Visits the enclosing class of the class.
`void`	`visitSource(java.lang.String file, java.lang.String debug)` Visits the source of the class.
`AnnotationVisitor`	`visitTypeAnnotation(int typeRef, TypePath typePath, java.lang.String desc, boolean visible)` Visits an annotation on a type in the class signature.

Methods inherited from class java.lang.Object
clone, equals, finalize, getClass, hashCode, notify, notifyAll, toString, wait, wait, wait

- Field Detail
  - COMPUTE_MAXS
```
public static final int COMPUTE_MAXS
```
    Flag to automatically compute the maximum stack size and the maximum number of local variables of methods. If this flag is set, then the arguments of the visitMaxs method of the MethodVisitor returned by the visitMethod method will be ignored, and computed automatically from the signature and the bytecode of each method.
    
    See Also:
    
    ClassWriter(int), Constant Field Values
  - COMPUTE_FRAMES
```
public static final int COMPUTE_FRAMES
```
    Flag to automatically compute the stack map frames of methods from scratch. If this flag is set, then the calls to the MethodVisitor.visitFrame(int, int, java.lang.Object[], int, java.lang.Object[]) method are ignored, and the stack map frames are recomputed from the methods bytecode. The arguments of the visitMaxs method are also ignored and recomputed from the bytecode. In other words, computeFrames implies computeMaxs.
    
    See Also:
    
    ClassWriter(int), Constant Field Values
  - ACC_SYNTHETIC_ATTRIBUTE
```
static final int ACC_SYNTHETIC_ATTRIBUTE
```
    Pseudo access flag to distinguish between the synthetic attribute and the synthetic access flag.
    
    See Also:
    
    Constant Field Values
  - TO_ACC_SYNTHETIC
```
static final int TO_ACC_SYNTHETIC
```
    Factor to convert from ACC_SYNTHETIC_ATTRIBUTE to Opcode.ACC_SYNTHETIC.
    
    See Also:
    
    Constant Field Values
  - NOARG_INSN
```
static final int NOARG_INSN
```
    The type of instructions without any argument.
    
    See Also:
    
    Constant Field Values
  - SBYTE_INSN
```
static final int SBYTE_INSN
```
    The type of instructions with an signed byte argument.
    
    See Also:
    
    Constant Field Values
  - SHORT_INSN
```
static final int SHORT_INSN
```
    The type of instructions with an signed short argument.
    
    See Also:
    
    Constant Field Values
  - VAR_INSN
```
static final int VAR_INSN
```
    The type of instructions with a local variable index argument.
    
    See Also:
    
    Constant Field Values
  - IMPLVAR_INSN
```
static final int IMPLVAR_INSN
```
    The type of instructions with an implicit local variable index argument.
    
    See Also:
    
    Constant Field Values
  - TYPE_INSN
```
static final int TYPE_INSN
```
    The type of instructions with a type descriptor argument.
    
    See Also:
    
    Constant Field Values
  - FIELDORMETH_INSN
```
static final int FIELDORMETH_INSN
```
    The type of field and method invocations instructions.
    
    See Also:
    
    Constant Field Values
  - ITFMETH_INSN
```
static final int ITFMETH_INSN
```
    The type of the INVOKEINTERFACE/INVOKEDYNAMIC instruction.
    
    See Also:
    
    Constant Field Values
  - INDYMETH_INSN
```
static final int INDYMETH_INSN
```
    The type of the INVOKEDYNAMIC instruction.
    
    See Also:
    
    Constant Field Values
  - LABEL_INSN
```
static final int LABEL_INSN
```
    The type of instructions with a 2 bytes bytecode offset label.
    
    See Also:
    
    Constant Field Values
  - LABELW_INSN
```
static final int LABELW_INSN
```
    The type of instructions with a 4 bytes bytecode offset label.
    
    See Also:
    
    Constant Field Values
  - LDC_INSN
```
static final int LDC_INSN
```
    The type of the LDC instruction.
    
    See Also:
    
    Constant Field Values
  - LDCW_INSN
```
static final int LDCW_INSN
```
    The type of the LDC_W and LDC2_W instructions.
    
    See Also:
    
    Constant Field Values
  - IINC_INSN
```
static final int IINC_INSN
```
    The type of the IINC instruction.
    
    See Also:
    
    Constant Field Values
  - TABL_INSN
```
static final int TABL_INSN
```
    The type of the TABLESWITCH instruction.
    
    See Also:
    
    Constant Field Values
  - LOOK_INSN
```
static final int LOOK_INSN
```
    The type of the LOOKUPSWITCH instruction.
    
    See Also:
    
    Constant Field Values
  - MANA_INSN
```
static final int MANA_INSN
```
    The type of the MULTIANEWARRAY instruction.
    
    See Also:
    
    Constant Field Values
  - WIDE_INSN
```
static final int WIDE_INSN
```
    The type of the WIDE instruction.
    
    See Also:
    
    Constant Field Values
  - TYPE
```
static final byte[] TYPE
```
    The instruction types of all JVM opcodes.
  - CLASS
```
static final int CLASS
```
    The type of CONSTANT_Class constant pool items.
    
    See Also:
    
    Constant Field Values
  - FIELD
```
static final int FIELD
```
    The type of CONSTANT_Fieldref constant pool items.
    
    See Also:
    
    Constant Field Values
  - METH
```
static final int METH
```
    The type of CONSTANT_Methodref constant pool items.
    
    See Also:
    
    Constant Field Values
  - IMETH
```
static final int IMETH
```
    The type of CONSTANT_InterfaceMethodref constant pool items.
    
    See Also:
    
    Constant Field Values
  - STR
```
static final int STR
```
    The type of CONSTANT_String constant pool items.
    
    See Also:
    
    Constant Field Values
  - INT
```
static final int INT
```
    The type of CONSTANT_Integer constant pool items.
    
    See Also:
    
    Constant Field Values
  - FLOAT
```
static final int FLOAT
```
    The type of CONSTANT_Float constant pool items.
    
    See Also:
    
    Constant Field Values
  - LONG
```
static final int LONG
```
    The type of CONSTANT_Long constant pool items.
    
    See Also:
    
    Constant Field Values
  - DOUBLE
```
static final int DOUBLE
```
    The type of CONSTANT_Double constant pool items.
    
    See Also:
    
    Constant Field Values
  - NAME_TYPE
```
static final int NAME_TYPE
```
    The type of CONSTANT_NameAndType constant pool items.
    
    See Also:
    
    Constant Field Values
  - UTF8
```
static final int UTF8
```
    The type of CONSTANT_Utf8 constant pool items.
    
    See Also:
    
    Constant Field Values
  - MTYPE
```
static final int MTYPE
```
    The type of CONSTANT_MethodType constant pool items.
    
    See Also:
    
    Constant Field Values
  - HANDLE
```
static final int HANDLE
```
    The type of CONSTANT_MethodHandle constant pool items.
    
    See Also:
    
    Constant Field Values
  - INDY
```
static final int INDY
```
    The type of CONSTANT_InvokeDynamic constant pool items.
    
    See Also:
    
    Constant Field Values
  - HANDLE_BASE
```
static final int HANDLE_BASE
```
    The base value for all CONSTANT_MethodHandle constant pool items. Internally, ASM store the 9 variations of CONSTANT_MethodHandle into 9 different items.
    
    See Also:
    
    Constant Field Values
  - TYPE_NORMAL
```
static final int TYPE_NORMAL
```
    Normal type Item stored in the ClassWriter typeTable, instead of the constant pool, in order to avoid clashes with normal constant pool items in the ClassWriter constant pool's hash table.
    
    See Also:
    
    Constant Field Values
  - TYPE_UNINIT
```
static final int TYPE_UNINIT
```
    Uninitialized type Item stored in the ClassWriter typeTable, instead of the constant pool, in order to avoid clashes with normal constant pool items in the ClassWriter constant pool's hash table.
    
    See Also:
    
    Constant Field Values
  - TYPE_MERGED
```
static final int TYPE_MERGED
```
    Merged type Item stored in the ClassWriter typeTable, instead of the constant pool, in order to avoid clashes with normal constant pool items in the ClassWriter constant pool's hash table.
    
    See Also:
    
    Constant Field Values
  - BSM
```
static final int BSM
```
    The type of BootstrapMethods items. These items are stored in a special class attribute named BootstrapMethods and not in the constant pool.
    
    See Also:
    
    Constant Field Values
  - cr
```
ClassReader cr
```
    The class reader from which this class writer was constructed, if any.
  - version
```
int version
```
    Minor and major version numbers of the class to be generated.
  - index
```
int index
```
    Index of the next item to be added in the constant pool.
  - pool
```
final ByteVector pool
```
    The constant pool of this class.
  - items
```
Item[] items
```
    The constant pool's hash table data.
  - threshold
```
int threshold
```
    The threshold of the constant pool's hash table.
  - key
```
final Item key
```
    A reusable key used to look for items in the items hash table.
  - key2
```
final Item key2
```
    A reusable key used to look for items in the items hash table.
  - key3
```
final Item key3
```
    A reusable key used to look for items in the items hash table.
  - key4
```
final Item key4
```
    A reusable key used to look for items in the items hash table.
  - typeTable
```
Item[] typeTable
```
    A type table used to temporarily store internal names that will not necessarily be stored in the constant pool. This type table is used by the control flow and data flow analysis algorithm used to compute stack map frames from scratch. This array associates to each index i the Item whose index is i. All Item objects stored in this array are also stored in the items hash table. These two arrays allow to retrieve an Item from its index or, conversely, to get the index of an Item from its value. Each Item stores an internal name in its Item.strVal1 field.
  - typeCount
```
private short typeCount
```
    Number of elements in the typeTable array.
  - access
```
private int access
```
    The access flags of this class.
  - name
```
private int name
```
    The constant pool item that contains the internal name of this class.
  - thisName
```
java.lang.String thisName
```
    The internal name of this class.
  - signature
```
private int signature
```
    The constant pool item that contains the signature of this class.
  - superName
```
private int superName
```
    The constant pool item that contains the internal name of the super class of this class.
  - interfaceCount
```
private int interfaceCount
```
    Number of interfaces implemented or extended by this class or interface.
  - interfaces
```
private int[] interfaces
```
    The interfaces implemented or extended by this class or interface. More precisely, this array contains the indexes of the constant pool items that contain the internal names of these interfaces.
  - sourceFile
```
private int sourceFile
```
    The index of the constant pool item that contains the name of the source file from which this class was compiled.
  - sourceDebug
```
private ByteVector sourceDebug
```
    The SourceDebug attribute of this class.
  - enclosingMethodOwner
```
private int enclosingMethodOwner
```
    The constant pool item that contains the name of the enclosing class of this class.
  - enclosingMethod
```
private int enclosingMethod
```
    The constant pool item that contains the name and descriptor of the enclosing method of this class.
  - anns
```
private AnnotationWriter anns
```
    The runtime visible annotations of this class.
  - ianns
```
private AnnotationWriter ianns
```
    The runtime invisible annotations of this class.
  - tanns
```
private AnnotationWriter tanns
```
    The runtime visible type annotations of this class.
  - itanns
```
private AnnotationWriter itanns
```
    The runtime invisible type annotations of this class.
  - attrs
```
private Attribute attrs
```
    The non standard attributes of this class.
  - innerClassesCount
```
private int innerClassesCount
```
    The number of entries in the InnerClasses attribute.
  - innerClasses
```
private ByteVector innerClasses
```
    The InnerClasses attribute.
  - bootstrapMethodsCount
```
int bootstrapMethodsCount
```
    The number of entries in the BootstrapMethods attribute.
  - bootstrapMethods
```
ByteVector bootstrapMethods
```
    The BootstrapMethods attribute.
  - firstField
```
FieldWriter firstField
```
    The fields of this class. These fields are stored in a linked list of FieldWriter objects, linked to each other by their FieldVisitor.fv field. This field stores the first element of this list.
  - lastField
```
FieldWriter lastField
```
    The fields of this class. These fields are stored in a linked list of FieldWriter objects, linked to each other by their FieldVisitor.fv field. This field stores the last element of this list.
  - firstMethod
```
MethodWriter firstMethod
```
    The methods of this class. These methods are stored in a linked list of MethodWriter objects, linked to each other by their MethodVisitor.mv field. This field stores the first element of this list.
  - lastMethod
```
MethodWriter lastMethod
```
    The methods of this class. These methods are stored in a linked list of MethodWriter objects, linked to each other by their MethodVisitor.mv field. This field stores the last element of this list.
  - computeMaxs
```
private boolean computeMaxs
```
    true if the maximum stack size and number of local variables must be automatically computed.
  - computeFrames
```
private boolean computeFrames
```
    true if the stack map frames must be recomputed from scratch.
  - invalidFrames
```
boolean invalidFrames
```
    true if the stack map tables of this class are invalid. The MethodWriter.resizeInstructions() method cannot transform existing stack map tables, and so produces potentially invalid classes when it is executed. In this case the class is reread and rewritten with the COMPUTE_FRAMES option (the resizeInstructions method can resize stack map tables when this option is used).
- Constructor Detail
  - ClassWriter
```
public ClassWriter(int flags)
```
    Constructs a new ClassWriter object.
    
    Parameters:
    
    flags - option flags that can be used to modify the default behavior of this class. See COMPUTE_MAXS, COMPUTE_FRAMES.
  - ClassWriter
```
public ClassWriter(ClassReader classReader,
                   int flags)
```
    Constructs a new ClassWriter object and enables optimizations for "mostly add" bytecode transformations. These optimizations are the following:
    - The constant pool from the original class is copied as is in the new class, which saves time. New constant pool entries will be added at the end if necessary, but unused constant pool entries won't be removed.
    - Methods that are not transformed are copied as is in the new class, directly from the original class bytecode (i.e. without emitting visit events for all the method instructions), which saves a lot of time. Untransformed methods are detected by the fact that the ClassReader receives MethodVisitor objects that come from a ClassWriter (and not from any other ClassVisitor instance).
    Parameters:
    
    classReader - the ClassReader used to read the original class. It will be used to copy the entire constant pool from the original class and also to copy other fragments of original bytecode where applicable.
    
    flags - option flags that can be used to modify the default behavior of this class. These option flags do not affect methods that are copied as is in the new class. This means that the maximum stack size nor the stack frames will be computed for these methods. See COMPUTE_MAXS, COMPUTE_FRAMES.
- Method Detail
  - visit
```
public final void visit(int version,
                        int access,
                        java.lang.String name,
                        java.lang.String signature,
                        java.lang.String superName,
                        java.lang.String[] interfaces)
```
    Description copied from class: ClassVisitor
    
    Visits the header of the class.
    
    Overrides:
    
    visit in class ClassVisitor
    
    Parameters:
    
    version - the class version.
    
    access - the class's access flags (see Opcodes). This parameter also indicates if the class is deprecated.
    
    name - the internal name of the class (see getInternalName).
    
    signature - the signature of this class. May be null if the class is not a generic one, and does not extend or implement generic classes or interfaces.
    
    superName - the internal of name of the super class (see getInternalName). For interfaces, the super class is Object. May be null, but only for the Object class.
    
    interfaces - the internal names of the class's interfaces (see getInternalName). May be null.
  - visitSource
```
public final void visitSource(java.lang.String file,
                              java.lang.String debug)
```
    Description copied from class: ClassVisitor
    
    Visits the source of the class.
    
    Overrides:
    
    visitSource in class ClassVisitor
    
    Parameters:
    
    file - the name of the source file from which the class was compiled. May be null.
    
    debug - additional debug information to compute the correspondance between source and compiled elements of the class. May be null.
  - visitOuterClass
```
public final void visitOuterClass(java.lang.String owner,
                                  java.lang.String name,
                                  java.lang.String desc)
```
    Description copied from class: ClassVisitor
    
    Visits the enclosing class of the class. This method must be called only if the class has an enclosing class.
    
    Overrides:
    
    visitOuterClass in class ClassVisitor
    
    Parameters:
    
    owner - internal name of the enclosing class of the class.
    
    name - the name of the method that contains the class, or null if the class is not enclosed in a method of its enclosing class.
    
    desc - the descriptor of the method that contains the class, or null if the class is not enclosed in a method of its enclosing class.
  - visitAnnotation
```
public final AnnotationVisitor visitAnnotation(java.lang.String desc,
                                               boolean visible)
```
    Description copied from class: ClassVisitor
    
    Visits an annotation of the class.
    
    Overrides:
    
    visitAnnotation in class ClassVisitor
    
    Parameters:
    
    desc - the class descriptor of the annotation class.
    
    visible - true if the annotation is visible at runtime.
    
    Returns:
    
    a visitor to visit the annotation values, or null if this visitor is not interested in visiting this annotation.
  - visitTypeAnnotation
```
public final AnnotationVisitor visitTypeAnnotation(int typeRef,
                                                   TypePath typePath,
                                                   java.lang.String desc,
                                                   boolean visible)
```
    Description copied from class: ClassVisitor
    
    Visits an annotation on a type in the class signature.
    
    Overrides:
    
    visitTypeAnnotation in class ClassVisitor
    
    Parameters:
    
    typeRef - a reference to the annotated type. The sort of this type reference must be CLASS_TYPE_PARAMETER, CLASS_TYPE_PARAMETER_BOUND or CLASS_EXTENDS. See TypeReference.
    
    typePath - the path to the annotated type argument, wildcard bound, array element type, or static inner type within 'typeRef'. May be null if the annotation targets 'typeRef' as a whole.
    
    desc - the class descriptor of the annotation class.
    
    visible - true if the annotation is visible at runtime.
    
    Returns:
    
    a visitor to visit the annotation values, or null if this visitor is not interested in visiting this annotation.
  - visitAttribute
```
public final void visitAttribute(Attribute attr)
```
    Description copied from class: ClassVisitor
    
    Visits a non standard attribute of the class.
    
    Overrides:
    
    visitAttribute in class ClassVisitor
    
    Parameters:
    
    attr - an attribute.
  - visitInnerClass
```
public final void visitInnerClass(java.lang.String name,
                                  java.lang.String outerName,
                                  java.lang.String innerName,
                                  int access)
```
    Description copied from class: ClassVisitor
    
    Visits information about an inner class. This inner class is not necessarily a member of the class being visited.
    
    Overrides:
    
    visitInnerClass in class ClassVisitor
    
    Parameters:
    
    name - the internal name of an inner class (see getInternalName).
    
    outerName - the internal name of the class to which the inner class belongs (see getInternalName). May be null for not member classes.
    
    innerName - the (simple) name of the inner class inside its enclosing class. May be null for anonymous inner classes.
    
    access - the access flags of the inner class as originally declared in the enclosing class.
  - visitField
```
public final FieldVisitor visitField(int access,
                                     java.lang.String name,
                                     java.lang.String desc,
                                     java.lang.String signature,
                                     java.lang.Object value)
```
    Description copied from class: ClassVisitor
    
    Visits a field of the class.
    
    Overrides:
    
    visitField in class ClassVisitor
    
    Parameters:
    
    access - the field's access flags (see Opcodes). This parameter also indicates if the field is synthetic and/or deprecated.
    
    name - the field's name.
    
    desc - the field's descriptor (see Type).
    
    signature - the field's signature. May be null if the field's type does not use generic types.
    
    value - the field's initial value. This parameter, which may be null if the field does not have an initial value, must be an Integer, a Float, a Long, a Double or a String (for int, float, long or String fields respectively). This parameter is only used for static fields. Its value is ignored for non static fields, which must be initialized through bytecode instructions in constructors or methods.
    
    Returns:
    
    a visitor to visit field annotations and attributes, or null if this class visitor is not interested in visiting these annotations and attributes.
  - visitMethod
```
public final MethodVisitor visitMethod(int access,
                                       java.lang.String name,
                                       java.lang.String desc,
                                       java.lang.String signature,
                                       java.lang.String[] exceptions)
```
    Description copied from class: ClassVisitor
    
    Visits a method of the class. This method must return a new MethodVisitor instance (or null) each time it is called, i.e., it should not return a previously returned visitor.
    
    Overrides:
    
    visitMethod in class ClassVisitor
    
    Parameters:
    
    access - the method's access flags (see Opcodes). This parameter also indicates if the method is synthetic and/or deprecated.
    
    name - the method's name.
    
    desc - the method's descriptor (see Type).
    
    signature - the method's signature. May be null if the method parameters, return type and exceptions do not use generic types.
    
    exceptions - the internal names of the method's exception classes (see getInternalName). May be null.
    
    Returns:
    
    an object to visit the byte code of the method, or null if this class visitor is not interested in visiting the code of this method.
  - visitEnd
```
public final void visitEnd()
```
    Description copied from class: ClassVisitor
    
    Visits the end of the class. This method, which is the last one to be called, is used to inform the visitor that all the fields and methods of the class have been visited.
    
    Overrides:
    
    visitEnd in class ClassVisitor
  - toByteArray
```
public byte[] toByteArray()
```
    Returns the bytecode of the class that was build with this class writer.
    
    Returns:
    
    the bytecode of the class that was build with this class writer.
  - newConstItem
```
Item newConstItem(java.lang.Object cst)
```
    Adds a number or string constant to the constant pool of the class being build. Does nothing if the constant pool already contains a similar item.
    
    Parameters:
    
    cst - the value of the constant to be added to the constant pool. This parameter must be an Integer, a Float, a Long, a Double, a String or a Type.
    
    Returns:
    
    a new or already existing constant item with the given value.
  - newConst
```
public int newConst(java.lang.Object cst)
```
    Adds a number or string constant to the constant pool of the class being build. Does nothing if the constant pool already contains a similar item. This method is intended for Attribute sub classes, and is normally not needed by class generators or adapters.
    
    Parameters:
    
    cst - the value of the constant to be added to the constant pool. This parameter must be an Integer, a Float, a Long, a Double or a String.
    
    Returns:
    
    the index of a new or already existing constant item with the given value.
  - newUTF8
```
public int newUTF8(java.lang.String value)
```
    Adds an UTF8 string to the constant pool of the class being build. Does nothing if the constant pool already contains a similar item. This method is intended for Attribute sub classes, and is normally not needed by class generators or adapters.
    
    Parameters:
    
    value - the String value.
    
    Returns:
    
    the index of a new or already existing UTF8 item.
  - newClassItem
```
Item newClassItem(java.lang.String value)
```
    Adds a class reference to the constant pool of the class being build. Does nothing if the constant pool already contains a similar item. This method is intended for Attribute sub classes, and is normally not needed by class generators or adapters.
    
    Parameters:
    
    value - the internal name of the class.
    
    Returns:
    
    a new or already existing class reference item.
  - newClass
```
public int newClass(java.lang.String value)
```
    Adds a class reference to the constant pool of the class being build. Does nothing if the constant pool already contains a similar item. This method is intended for Attribute sub classes, and is normally not needed by class generators or adapters.
    
    Parameters:
    
    value - the internal name of the class.
    
    Returns:
    
    the index of a new or already existing class reference item.
  - newMethodTypeItem
```
Item newMethodTypeItem(java.lang.String methodDesc)
```
    Adds a method type reference to the constant pool of the class being build. Does nothing if the constant pool already contains a similar item. This method is intended for Attribute sub classes, and is normally not needed by class generators or adapters.
    
    Parameters:
    
    methodDesc - method descriptor of the method type.
    
    Returns:
    
    a new or already existing method type reference item.
  - newMethodType
```
public int newMethodType(java.lang.String methodDesc)
```
    Adds a method type reference to the constant pool of the class being build. Does nothing if the constant pool already contains a similar item. This method is intended for Attribute sub classes, and is normally not needed by class generators or adapters.
    
    Parameters:
    
    methodDesc - method descriptor of the method type.
    
    Returns:
    
    the index of a new or already existing method type reference item.
  - newHandleItem
```
Item newHandleItem(int tag,
                   java.lang.String owner,
                   java.lang.String name,
                   java.lang.String desc)
```
    Adds a handle to the constant pool of the class being build. Does nothing if the constant pool already contains a similar item. This method is intended for Attribute sub classes, and is normally not needed by class generators or adapters.
    
    Parameters:
    
    tag - the kind of this handle. Must be Opcodes.H_GETFIELD, Opcodes.H_GETSTATIC, Opcodes.H_PUTFIELD, Opcodes.H_PUTSTATIC, Opcodes.H_INVOKEVIRTUAL, Opcodes.H_INVOKESTATIC, Opcodes.H_INVOKESPECIAL, Opcodes.H_NEWINVOKESPECIAL or Opcodes.H_INVOKEINTERFACE.
    
    owner - the internal name of the field or method owner class.
    
    name - the name of the field or method.
    
    desc - the descriptor of the field or method.
    
    Returns:
    
    a new or an already existing method type reference item.
  - newHandle
```
public int newHandle(int tag,
                     java.lang.String owner,
                     java.lang.String name,
                     java.lang.String desc)
```
    Adds a handle to the constant pool of the class being build. Does nothing if the constant pool already contains a similar item. This method is intended for Attribute sub classes, and is normally not needed by class generators or adapters.
    
    Parameters:
    
    tag - the kind of this handle. Must be Opcodes.H_GETFIELD, Opcodes.H_GETSTATIC, Opcodes.H_PUTFIELD, Opcodes.H_PUTSTATIC, Opcodes.H_INVOKEVIRTUAL, Opcodes.H_INVOKESTATIC, Opcodes.H_INVOKESPECIAL, Opcodes.H_NEWINVOKESPECIAL or Opcodes.H_INVOKEINTERFACE.
    
    owner - the internal name of the field or method owner class.
    
    name - the name of the field or method.
    
    desc - the descriptor of the field or method.
    
    Returns:
    
    the index of a new or already existing method type reference item.
  - newInvokeDynamicItem
```
Item newInvokeDynamicItem(java.lang.String name,
                          java.lang.String desc,
                          Handle bsm,
                          java.lang.Object... bsmArgs)
```
    Adds an invokedynamic reference to the constant pool of the class being build. Does nothing if the constant pool already contains a similar item. This method is intended for Attribute sub classes, and is normally not needed by class generators or adapters.
    
    Parameters:
    
    name - name of the invoked method.
    
    desc - descriptor of the invoke method.
    
    bsm - the bootstrap method.
    
    bsmArgs - the bootstrap method constant arguments.
    
    Returns:
    
    a new or an already existing invokedynamic type reference item.
  - newInvokeDynamic
```
public int newInvokeDynamic(java.lang.String name,
                            java.lang.String desc,
                            Handle bsm,
                            java.lang.Object... bsmArgs)
```
    Adds an invokedynamic reference to the constant pool of the class being build. Does nothing if the constant pool already contains a similar item. This method is intended for Attribute sub classes, and is normally not needed by class generators or adapters.
    
    Parameters:
    
    name - name of the invoked method.
    
    desc - descriptor of the invoke method.
    
    bsm - the bootstrap method.
    
    bsmArgs - the bootstrap method constant arguments.
    
    Returns:
    
    the index of a new or already existing invokedynamic reference item.
  - newFieldItem
```
Item newFieldItem(java.lang.String owner,
                  java.lang.String name,
                  java.lang.String desc)
```
    Adds a field reference to the constant pool of the class being build. Does nothing if the constant pool already contains a similar item.
    
    Parameters:
    
    owner - the internal name of the field's owner class.
    
    name - the field's name.
    
    desc - the field's descriptor.
    
    Returns:
    
    a new or already existing field reference item.
  - newField
```
public int newField(java.lang.String owner,
                    java.lang.String name,
                    java.lang.String desc)
```
    Adds a field reference to the constant pool of the class being build. Does nothing if the constant pool already contains a similar item. This method is intended for Attribute sub classes, and is normally not needed by class generators or adapters.
    
    Parameters:
    
    owner - the internal name of the field's owner class.
    
    name - the field's name.
    
    desc - the field's descriptor.
    
    Returns:
    
    the index of a new or already existing field reference item.
  - newMethodItem
```
Item newMethodItem(java.lang.String owner,
                   java.lang.String name,
                   java.lang.String desc,
                   boolean itf)
```
    Adds a method reference to the constant pool of the class being build. Does nothing if the constant pool already contains a similar item.
    
    Parameters:
    
    owner - the internal name of the method's owner class.
    
    name - the method's name.
    
    desc - the method's descriptor.
    
    itf - true if owner is an interface.
    
    Returns:
    
    a new or already existing method reference item.
  - newMethod
```
public int newMethod(java.lang.String owner,
                     java.lang.String name,
                     java.lang.String desc,
                     boolean itf)
```
    Adds a method reference to the constant pool of the class being build. Does nothing if the constant pool already contains a similar item. This method is intended for Attribute sub classes, and is normally not needed by class generators or adapters.
    
    Parameters:
    
    owner - the internal name of the method's owner class.
    
    name - the method's name.
    
    desc - the method's descriptor.
    
    itf - true if owner is an interface.
    
    Returns:
    
    the index of a new or already existing method reference item.
  - newInteger
```
Item newInteger(int value)
```
    Adds an integer to the constant pool of the class being build. Does nothing if the constant pool already contains a similar item.
    
    Parameters:
    
    value - the int value.
    
    Returns:
    
    a new or already existing int item.
  - newFloat
```
Item newFloat(float value)
```
    Adds a float to the constant pool of the class being build. Does nothing if the constant pool already contains a similar item.
    
    Parameters:
    
    value - the float value.
    
    Returns:
    
    a new or already existing float item.
  - newLong
```
Item newLong(long value)
```
    Adds a long to the constant pool of the class being build. Does nothing if the constant pool already contains a similar item.
    
    Parameters:
    
    value - the long value.
    
    Returns:
    
    a new or already existing long item.
  - newDouble
```
Item newDouble(double value)
```
    Adds a double to the constant pool of the class being build. Does nothing if the constant pool already contains a similar item.
    
    Parameters:
    
    value - the double value.
    
    Returns:
    
    a new or already existing double item.
  - newString
```
private Item newString(java.lang.String value)
```
    Adds a string to the constant pool of the class being build. Does nothing if the constant pool already contains a similar item.
    
    Parameters:
    
    value - the String value.
    
    Returns:
    
    a new or already existing string item.
  - newNameType
```
public int newNameType(java.lang.String name,
                       java.lang.String desc)
```
    Adds a name and type to the constant pool of the class being build. Does nothing if the constant pool already contains a similar item. This method is intended for Attribute sub classes, and is normally not needed by class generators or adapters.
    
    Parameters:
    
    name - a name.
    
    desc - a type descriptor.
    
    Returns:
    
    the index of a new or already existing name and type item.
  - newNameTypeItem
```
Item newNameTypeItem(java.lang.String name,
                     java.lang.String desc)
```
    Adds a name and type to the constant pool of the class being build. Does nothing if the constant pool already contains a similar item.
    
    Parameters:
    
    name - a name.
    
    desc - a type descriptor.
    
    Returns:
    
    a new or already existing name and type item.
  - addType
```
int addType(java.lang.String type)
```
    Adds the given internal name to typeTable and returns its index. Does nothing if the type table already contains this internal name.
    
    Parameters:
    
    type - the internal name to be added to the type table.
    
    Returns:
    
    the index of this internal name in the type table.
  - addUninitializedType
```
int addUninitializedType(java.lang.String type,
                         int offset)
```
    Adds the given "uninitialized" type to typeTable and returns its index. This method is used for UNINITIALIZED types, made of an internal name and a bytecode offset.
    
    Parameters:
    
    type - the internal name to be added to the type table.
    
    offset - the bytecode offset of the NEW instruction that created this UNINITIALIZED type value.
    
    Returns:
    
    the index of this internal name in the type table.
  - addType
```
private Item addType(Item item)
```
    Adds the given Item to typeTable.
    
    Parameters:
    
    item - the value to be added to the type table.
    
    Returns:
    
    the added Item, which a new Item instance with the same value as the given Item.
  - getMergedType
```
int getMergedType(int type1,
                  int type2)
```
    Returns the index of the common super type of the two given types. This method calls getCommonSuperClass(java.lang.String, java.lang.String) and caches the result in the items hash table to speedup future calls with the same parameters.
    
    Parameters:
    
    type1 - index of an internal name in typeTable.
    
    type2 - index of an internal name in typeTable.
    
    Returns:
    
    the index of the common super type of the two given types.
  - getCommonSuperClass
```
protected java.lang.String getCommonSuperClass(java.lang.String type1,
                                               java.lang.String type2)
```
    Returns the common super type of the two given types. The default implementation of this method loads the two given classes and uses the java.lang.Class methods to find the common super class. It can be overridden to compute this common super type in other ways, in particular without actually loading any class, or to take into account the class that is currently being generated by this ClassWriter, which can of course not be loaded since it is under construction.
    
    Parameters:
    
    type1 - the internal name of a class.
    
    type2 - the internal name of another class.
    
    Returns:
    
    the internal name of the common super class of the two given classes.
  - get
```
private Item get(Item key)
```
    Returns the constant pool's hash table item which is equal to the given item.
    
    Parameters:
    
    key - a constant pool item.
    
    Returns:
    
    the constant pool's hash table item which is equal to the given item, or null if there is no such item.
  - put
```
private void put(Item i)
```
    Puts the given item in the constant pool's hash table. The hash table must not already contains this item.
    
    Parameters:
    
    i - the item to be added to the constant pool's hash table.
  - put122
```
private void put122(int b,
                    int s1,
                    int s2)
```
    Puts one byte and two shorts into the constant pool.
    
    Parameters:
    
    b - a byte.
    
    s1 - a short.
    
    s2 - another short.
  - put112
```
private void put112(int b1,
                    int b2,
                    int s)
```
    Puts two bytes and one short into the constant pool.
    
    Parameters:
    
    b1 - a byte.
    
    b2 - another byte.
    
    s - a short.

Class ClassWriter

Field Summary

Fields inherited from class org.springframework.asm.ClassVisitor

Constructor Summary

Method Summary

Methods inherited from class java.lang.Object

Field Detail

COMPUTE_MAXS

COMPUTE_FRAMES

ACC_SYNTHETIC_ATTRIBUTE

TO_ACC_SYNTHETIC

NOARG_INSN

SBYTE_INSN

SHORT_INSN

VAR_INSN

IMPLVAR_INSN

TYPE_INSN

FIELDORMETH_INSN

ITFMETH_INSN

INDYMETH_INSN

LABEL_INSN

LABELW_INSN

LDC_INSN

LDCW_INSN

IINC_INSN

TABL_INSN

LOOK_INSN

MANA_INSN

WIDE_INSN

TYPE

CLASS

FIELD

METH

IMETH

STR

INT

FLOAT

LONG

DOUBLE

NAME_TYPE

UTF8

MTYPE

HANDLE

INDY

HANDLE_BASE

TYPE_NORMAL

TYPE_UNINIT

TYPE_MERGED

BSM

cr

version

index

pool

items

threshold

key

key2

key3

key4

typeTable

typeCount

access

name

thisName

signature

superName

interfaceCount

interfaces

sourceFile

sourceDebug

enclosingMethodOwner

enclosingMethod

anns

ianns

tanns

itanns

attrs

innerClassesCount

innerClasses

bootstrapMethodsCount