Package org.springframework.expression.spel.ast

Class OperatorInstanceof

java.lang.Object

org.springframework.expression.spel.ast.SpelNodeImpl

org.springframework.expression.spel.ast.Operator

org.springframework.expression.spel.ast.OperatorInstanceof

All Implemented Interfaces:

Opcodes, SpelNode

public class OperatorInstanceof
extends Operator

The operator 'instanceof' checks if an object is of the class specified in the right-hand operand, in the same way that instanceof does in Java.

Since:

3.0

Author:

Andy Clement

Nested Class Summary

Nested classes/interfaces inherited from class org.springframework.expression.spel.ast.Operator

Operator.DescriptorComparison

Field Summary

Fields inherited from class org.springframework.expression.spel.ast.Operator

leftActualDescriptor, rightActualDescriptor

Fields inherited from class org.springframework.expression.spel.ast.SpelNodeImpl

children, exitTypeDescriptor

Fields inherited from interface org.springframework.asm.Opcodes

AALOAD, AASTORE, ACC_ABSTRACT, ACC_ANNOTATION, ACC_BRIDGE, ACC_DEPRECATED, ACC_ENUM, ACC_FINAL, ACC_INTERFACE, ACC_MANDATED, ACC_MODULE, ACC_NATIVE, ACC_OPEN, ACC_PRIVATE, ACC_PROTECTED, ACC_PUBLIC, ACC_RECORD, ACC_STATIC, ACC_STATIC_PHASE, ACC_STRICT, ACC_SUPER, ACC_SYNCHRONIZED, ACC_SYNTHETIC, ACC_TRANSIENT, ACC_TRANSITIVE, ACC_VARARGS, ACC_VOLATILE, ACONST_NULL, ALOAD, ANEWARRAY, ARETURN, ARRAYLENGTH, ASM10_EXPERIMENTAL, ASM4, ASM5, ASM6, ASM7, ASM8, ASM9, ASTORE, ATHROW, BALOAD, BASTORE, BIPUSH, CALOAD, CASTORE, CHECKCAST, D2F, D2I, D2L, DADD, DALOAD, DASTORE, DCMPG, DCMPL, DCONST_0, DCONST_1, DDIV, DLOAD, DMUL, DNEG, DOUBLE, DREM, DRETURN, DSTORE, DSUB, DUP, DUP_X1, DUP_X2, DUP2, DUP2_X1, DUP2_X2, F_APPEND, F_CHOP, F_FULL, F_NEW, F_SAME, F_SAME1, F2D, F2I, F2L, FADD, FALOAD, FASTORE, FCMPG, FCMPL, FCONST_0, FCONST_1, FCONST_2, FDIV, FLOAD, FLOAT, FMUL, FNEG, FREM, FRETURN, FSTORE, FSUB, GETFIELD, GETSTATIC, GOTO, H_GETFIELD, H_GETSTATIC, H_INVOKEINTERFACE, H_INVOKESPECIAL, H_INVOKESTATIC, H_INVOKEVIRTUAL, H_NEWINVOKESPECIAL, H_PUTFIELD, H_PUTSTATIC, I2B, I2C, I2D, I2F, I2L, I2S, IADD, IALOAD, IAND, IASTORE, ICONST_0, ICONST_1, ICONST_2, ICONST_3, ICONST_4, ICONST_5, ICONST_M1, IDIV, IF_ACMPEQ, IF_ACMPNE, IF_ICMPEQ, IF_ICMPGE, IF_ICMPGT, IF_ICMPLE, IF_ICMPLT, IF_ICMPNE, IFEQ, IFGE, IFGT, IFLE, IFLT, IFNE, IFNONNULL, IFNULL, IINC, ILOAD, IMUL, INEG, INSTANCEOF, INTEGER, INVOKEDYNAMIC, INVOKEINTERFACE, INVOKESPECIAL, INVOKESTATIC, INVOKEVIRTUAL, IOR, IREM, IRETURN, ISHL, ISHR, ISTORE, ISUB, IUSHR, IXOR, JSR, L2D, L2F, L2I, LADD, LALOAD, LAND, LASTORE, LCMP, LCONST_0, LCONST_1, LDC, LDIV, LLOAD, LMUL, LNEG, LONG, LOOKUPSWITCH, LOR, LREM, LRETURN, LSHL, LSHR, LSTORE, LSUB, LUSHR, LXOR, MONITORENTER, MONITOREXIT, MULTIANEWARRAY, NEW, NEWARRAY, NOP, NULL, POP, POP2, PUTFIELD, PUTSTATIC, RET, RETURN, SALOAD, SASTORE, SIPUSH, SOURCE_DEPRECATED, SOURCE_MASK, SWAP, T_BOOLEAN, T_BYTE, T_CHAR, T_DOUBLE, T_FLOAT, T_INT, T_LONG, T_SHORT, TABLESWITCH, TOP, UNINITIALIZED_THIS, V_PREVIEW, V1_1, V1_2, V1_3, V1_4, V1_5, V1_6, V1_7, V1_8, V10, V11, V12, V13, V14, V15, V16, V17, V18, V19, V20, V21, V22, V23, V24, V9

Constructor Summary

Constructors

Constructor	Description
OperatorInstanceof(int startPos, int endPos, SpelNodeImpl... operands)

Method Summary

Modifier and Type	Method	Description
void	generateCode(MethodVisitor mv, CodeFlow cf)	Generate the bytecode for this node into the supplied MethodVisitor.
BooleanTypedValue	getValueInternal(ExpressionState state)	Compare the left operand to see it is an instance of the type specified as the right operand.
boolean	isCompilable()	Determine if this node can be compiled to bytecode.

Methods inherited from class org.springframework.expression.spel.ast.Operator

equalityCheck, generateComparisonCode, getLeftOperand, getOperatorName, getRightOperand, isCompilableOperatorUsingNumerics, toStringAST

Methods inherited from class org.springframework.expression.spel.ast.SpelNodeImpl

generateCodeForArgument, generateCodeForArguments, generateCodeForArguments, getChild, getChildCount, getEndPosition, getExitDescriptor, getObjectClass, getStartPosition, getTypedValue, getValue, getValue, getValueRef, isNullSafe, isWritable, nextChildIs, setValue, setValueInternal

Methods inherited from class java.lang.Object

clone, equals, finalize, getClass, hashCode, notify, notifyAll, toString, wait, wait, wait

Constructor Details

OperatorInstanceof

public OperatorInstanceof(int startPos,
 int endPos,
 SpelNodeImpl... operands)

Method Details

getValueInternal

public BooleanTypedValue getValueInternal(ExpressionState state)
                                   throws EvaluationException

Compare the left operand to see it is an instance of the type specified as the right operand. The right operand must be a class.

Specified by:

getValueInternal in class SpelNodeImpl

Parameters:

state - the expression state

Returns:

true if the left operand is an instanceof of the right operand, otherwise false

Throws:

EvaluationException - if there is a problem evaluating the expression

isCompilable

public boolean isCompilable()

Description copied from interface: SpelNode

Determine if this node can be compiled to bytecode.

The reasoning in each node may be different but will typically involve checking whether the exit type descriptor of the node is known and any relevant child nodes are compilable.

The default implementation returns false.

If you override this method, you must also override SpelNode.generateCode(MethodVisitor, CodeFlow).

Returns:

true if this node can be compiled to bytecode

See Also:

• SpelNode.generateCode(MethodVisitor, CodeFlow)

generateCode

public void generateCode(MethodVisitor mv,
 CodeFlow cf)

Description copied from interface: SpelNode

Generate the bytecode for this node into the supplied MethodVisitor.

Context information about the current expression being compiled is available in the supplied CodeFlow object — for example, information about the type of the object currently on the stack.

This method will not be invoked unless SpelNode.isCompilable() returns true.

The default implementation throws an IllegalStateException since SpelNode.isCompilable() returns false by default.

If you override this method, you must also override SpelNode.isCompilable().

Parameters:

mv - the ASM MethodVisitor into which code should be generated

cf - a context object with information about what is on the stack

See Also:

• SpelNode.isCompilable()