Spring Framework

org.springframework.core
Class MethodParameter

java.lang.Object
  extended by org.springframework.core.MethodParameter

public class MethodParameter
extends java.lang.Object

Helper class that encapsulates the specification of a method parameter, i.e. a Method or Constructor plus a parameter index and a nested type index for a declared generic type. Useful as a specification object to pass along.

Since:
2.0
Author:
Juergen Hoeller, Rob Harrop, Andy Clement, Nikita Tovstoles, Chris Beams
See Also:
GenericCollectionTypeResolver

Constructor Summary
MethodParameter(java.lang.reflect.Constructor constructor, int parameterIndex)
          Create a new MethodParameter for the given constructor, with nesting level 1.
MethodParameter(java.lang.reflect.Constructor constructor, int parameterIndex, int nestingLevel)
          Create a new MethodParameter for the given constructor.
MethodParameter(java.lang.reflect.Method method, int parameterIndex)
          Create a new MethodParameter for the given method, with nesting level 1.
MethodParameter(java.lang.reflect.Method method, int parameterIndex, int nestingLevel)
          Create a new MethodParameter for the given method.
MethodParameter(MethodParameter original)
          Copy constructor, resulting in an independent MethodParameter object based on the same metadata and cache state that the original object was in.
 
Method Summary
 void decreaseNestingLevel()
          Decrease this parameter's nesting level.
 boolean equals(java.lang.Object obj)
           
static MethodParameter forMethodOrConstructor(java.lang.Object methodOrConstructor, int parameterIndex)
          Create a new MethodParameter for the given method or constructor.
 java.lang.reflect.Constructor getConstructor()
          Return the wrapped Constructor, if any.
 java.lang.Class getDeclaringClass()
          Return the class that declares the underlying Method or Constructor.
 java.lang.reflect.Type getGenericParameterType()
          Return the generic type of the method/constructor parameter.
 java.lang.reflect.Method getMethod()
          Return the wrapped Method, if any.
<T extends java.lang.annotation.Annotation>
T
getMethodAnnotation(java.lang.Class<T> annotationType)
          Return the method/constructor annotation of the given type, if available.
 java.lang.annotation.Annotation[] getMethodAnnotations()
          Return the annotations associated with the target method/constructor itself.
 java.lang.Class<?> getNestedParameterType()
           
 int getNestingLevel()
          Return the nesting level of the target type (typically 1; e.g.
<T extends java.lang.annotation.Annotation>
T
getParameterAnnotation(java.lang.Class<T> annotationType)
          Return the parameter annotation of the given type, if available.
 java.lang.annotation.Annotation[] getParameterAnnotations()
          Return the annotations associated with the specific method/constructor parameter.
 int getParameterIndex()
          Return the index of the method/constructor parameter.
 java.lang.String getParameterName()
          Return the name of the method/constructor parameter.
 java.lang.Class<?> getParameterType()
          Return the type of the method/constructor parameter.
 java.lang.Integer getTypeIndexForCurrentLevel()
          Return the type index for the current nesting level.
 java.lang.Integer getTypeIndexForLevel(int nestingLevel)
          Return the type index for the specified nesting level.
 int hashCode()
           
<T extends java.lang.annotation.Annotation>
boolean
hasParameterAnnotation(java.lang.Class<T> annotationType)
          Return true if the parameter has the given annotation type, and false if it doesn't.
 boolean hasParameterAnnotations()
          Return true if the parameter has at least one annotation, false if it has none.
 void increaseNestingLevel()
          Increase this parameter's nesting level.
 void initParameterNameDiscovery(ParameterNameDiscoverer parameterNameDiscoverer)
          Initialize parameter name discovery for this method parameter.
 void setTypeIndexForCurrentLevel(int typeIndex)
          Set the type index for the current nesting level.
 
Methods inherited from class java.lang.Object
clone, finalize, getClass, notify, notifyAll, toString, wait, wait, wait
 

Constructor Detail

MethodParameter

public MethodParameter(java.lang.reflect.Method method,
                       int parameterIndex)
Create a new MethodParameter for the given method, with nesting level 1.

Parameters:
method - the Method to specify a parameter for
parameterIndex - the index of the parameter

MethodParameter

public MethodParameter(java.lang.reflect.Method method,
                       int parameterIndex,
                       int nestingLevel)
Create a new MethodParameter for the given method.

Parameters:
method - the Method to specify a parameter for
parameterIndex - the index of the parameter (-1 for the method return type; 0 for the first method parameter, 1 for the second method parameter, etc)
nestingLevel - the nesting level of the target type (typically 1; e.g. in case of a List of Lists, 1 would indicate the nested List, whereas 2 would indicate the element of the nested List)

MethodParameter

public MethodParameter(java.lang.reflect.Constructor constructor,
                       int parameterIndex)
Create a new MethodParameter for the given constructor, with nesting level 1.

Parameters:
constructor - the Constructor to specify a parameter for
parameterIndex - the index of the parameter

MethodParameter

public MethodParameter(java.lang.reflect.Constructor constructor,
                       int parameterIndex,
                       int nestingLevel)
Create a new MethodParameter for the given constructor.

Parameters:
constructor - the Constructor to specify a parameter for
parameterIndex - the index of the parameter
nestingLevel - the nesting level of the target type (typically 1; e.g. in case of a List of Lists, 1 would indicate the nested List, whereas 2 would indicate the element of the nested List)

MethodParameter

public MethodParameter(MethodParameter original)
Copy constructor, resulting in an independent MethodParameter object based on the same metadata and cache state that the original object was in.

Parameters:
original - the original MethodParameter object to copy from
Method Detail

getMethod

public java.lang.reflect.Method getMethod()
Return the wrapped Method, if any.

Note: Either Method or Constructor is available.

Returns:
the Method, or null if none

getConstructor

public java.lang.reflect.Constructor getConstructor()
Return the wrapped Constructor, if any.

Note: Either Method or Constructor is available.

Returns:
the Constructor, or null if none

getDeclaringClass

public java.lang.Class getDeclaringClass()
Return the class that declares the underlying Method or Constructor.


getParameterIndex

public int getParameterIndex()
Return the index of the method/constructor parameter.

Returns:
the parameter index (never negative)

getParameterType

public java.lang.Class<?> getParameterType()
Return the type of the method/constructor parameter.

Returns:
the parameter type (never null)

getGenericParameterType

public java.lang.reflect.Type getGenericParameterType()
Return the generic type of the method/constructor parameter.

Returns:
the parameter type (never null)

getNestedParameterType

public java.lang.Class<?> getNestedParameterType()

getMethodAnnotations

public java.lang.annotation.Annotation[] getMethodAnnotations()
Return the annotations associated with the target method/constructor itself.


getMethodAnnotation

public <T extends java.lang.annotation.Annotation> T getMethodAnnotation(java.lang.Class<T> annotationType)
Return the method/constructor annotation of the given type, if available.

Parameters:
annotationType - the annotation type to look for
Returns:
the annotation object, or null if not found

getParameterAnnotations

public java.lang.annotation.Annotation[] getParameterAnnotations()
Return the annotations associated with the specific method/constructor parameter.


getParameterAnnotation

public <T extends java.lang.annotation.Annotation> T getParameterAnnotation(java.lang.Class<T> annotationType)
Return the parameter annotation of the given type, if available.

Parameters:
annotationType - the annotation type to look for
Returns:
the annotation object, or null if not found

hasParameterAnnotations

public boolean hasParameterAnnotations()
Return true if the parameter has at least one annotation, false if it has none.


hasParameterAnnotation

public <T extends java.lang.annotation.Annotation> boolean hasParameterAnnotation(java.lang.Class<T> annotationType)
Return true if the parameter has the given annotation type, and false if it doesn't.


initParameterNameDiscovery

public void initParameterNameDiscovery(ParameterNameDiscoverer parameterNameDiscoverer)
Initialize parameter name discovery for this method parameter.

This method does not actually try to retrieve the parameter name at this point; it just allows discovery to happen when the application calls getParameterName() (if ever).


getParameterName

public java.lang.String getParameterName()
Return the name of the method/constructor parameter.

Returns:
the parameter name (may be null if no parameter name metadata is contained in the class file or no ParameterNameDiscoverer has been set to begin with)

increaseNestingLevel

public void increaseNestingLevel()
Increase this parameter's nesting level.

See Also:
getNestingLevel()

decreaseNestingLevel

public void decreaseNestingLevel()
Decrease this parameter's nesting level.

See Also:
getNestingLevel()

getNestingLevel

public int getNestingLevel()
Return the nesting level of the target type (typically 1; e.g. in case of a List of Lists, 1 would indicate the nested List, whereas 2 would indicate the element of the nested List).


setTypeIndexForCurrentLevel

public void setTypeIndexForCurrentLevel(int typeIndex)
Set the type index for the current nesting level.

Parameters:
typeIndex - the corresponding type index (or null for the default type index)
See Also:
getNestingLevel()

getTypeIndexForCurrentLevel

public java.lang.Integer getTypeIndexForCurrentLevel()
Return the type index for the current nesting level.

Returns:
the corresponding type index, or null if none specified (indicating the default type index)
See Also:
getNestingLevel()

getTypeIndexForLevel

public java.lang.Integer getTypeIndexForLevel(int nestingLevel)
Return the type index for the specified nesting level.

Parameters:
nestingLevel - the nesting level to check
Returns:
the corresponding type index, or null if none specified (indicating the default type index)

forMethodOrConstructor

public static MethodParameter forMethodOrConstructor(java.lang.Object methodOrConstructor,
                                                     int parameterIndex)
Create a new MethodParameter for the given method or constructor.

This is a convenience constructor for scenarios where a Method or Constructor reference is treated in a generic fashion.

Parameters:
methodOrConstructor - the Method or Constructor to specify a parameter for
parameterIndex - the index of the parameter
Returns:
the corresponding MethodParameter instance

equals

public boolean equals(java.lang.Object obj)
Overrides:
equals in class java.lang.Object

hashCode

public int hashCode()
Overrides:
hashCode in class java.lang.Object

Spring Framework