org.apache.commons.beanutils
Class MethodUtils

java.lang.Object
  extended by org.apache.commons.beanutils.MethodUtils

public class MethodUtils
extends java.lang.Object

Utility reflection methods focussed on methods in general rather than properties in particular.

Known Limitations

Accessing Public Methods In A Default Access Superclass

There is an issue when invoking public methods contained in a default access superclass. Reflection locates these methods fine and correctly assigns them as public. However, an IllegalAccessException is thrown if the method is invoked.

MethodUtils contains a workaround for this situation. It will attempt to call setAccessible on this method. If this call succeeds, then the method can be invoked as normal. This call will only succeed when the application has sufficient security privilages. If this call fails then a warning will be logged and the method may fail.

Author:
Craig R. McClanahan, Ralph Schaer, Chris Audley, Rey François, Gregor Raýman, Jan Sorensen, Robert Burrell Donkin

Nested Class Summary
private static class MethodUtils.MethodDescriptor
          Represents the key to looking up a Method by reflection.
 
Field Summary
private static WeakFastHashMap cache
          Stores a cache of MethodDescriptor -> Method in a WeakHashMap.
private static boolean CACHE_METHODS
          Indicates whether methods should be cached for improved performance.
private static java.lang.Class[] EMPTY_CLASS_PARAMETERS
          An empty class array
private static java.lang.Object[] EMPTY_OBJECT_ARRAY
          An empty object array
private static boolean loggedAccessibleWarning
          Only log warning about accessibility work around once.
 
Constructor Summary
MethodUtils()
           
 
Method Summary
private static void cacheMethod(MethodUtils.MethodDescriptor md, java.lang.reflect.Method method)
          Add a method to the cache.
static int clearCache()
          Clear the method cache.
static java.lang.reflect.Method getAccessibleMethod(java.lang.Class clazz, java.lang.reflect.Method method)
          Return an accessible method (that is, one that can be invoked via reflection) that implements the specified Method.
static java.lang.reflect.Method getAccessibleMethod(java.lang.Class clazz, java.lang.String methodName, java.lang.Class parameterType)
          Return an accessible method (that is, one that can be invoked via reflection) with given name and a single parameter.
static java.lang.reflect.Method getAccessibleMethod(java.lang.Class clazz, java.lang.String methodName, java.lang.Class[] parameterTypes)
          Return an accessible method (that is, one that can be invoked via reflection) with given name and parameters.
static java.lang.reflect.Method getAccessibleMethod(java.lang.reflect.Method method)
          Return an accessible method (that is, one that can be invoked via reflection) that implements the specified Method.
private static java.lang.reflect.Method getAccessibleMethodFromInterfaceNest(java.lang.Class clazz, java.lang.String methodName, java.lang.Class[] parameterTypes)
          Return an accessible method (that is, one that can be invoked via reflection) that implements the specified method, by scanning through all implemented interfaces and subinterfaces.
private static java.lang.reflect.Method getAccessibleMethodFromSuperclass(java.lang.Class clazz, java.lang.String methodName, java.lang.Class[] parameterTypes)
          Return an accessible method (that is, one that can be invoked via reflection) by scanning through the superclasses.
private static java.lang.reflect.Method getCachedMethod(MethodUtils.MethodDescriptor md)
          Return the method from the cache, if present.
static java.lang.reflect.Method getMatchingAccessibleMethod(java.lang.Class clazz, java.lang.String methodName, java.lang.Class[] parameterTypes)
          Find an accessible method that matches the given name and has compatible parameters.
private static float getObjectTransformationCost(java.lang.Class srcClass, java.lang.Class destClass)
          Gets the number of steps required needed to turn the source class into the destination class.
static java.lang.Class getPrimitiveType(java.lang.Class wrapperType)
          Gets the class for the primitive type corresponding to the primitive wrapper class given.
static java.lang.Class getPrimitiveWrapper(java.lang.Class primitiveType)
          Gets the wrapper object class for the given primitive type class.
private static float getTotalTransformationCost(java.lang.Class[] srcArgs, java.lang.Class[] destArgs)
          Returns the sum of the object transformation cost for each class in the source argument list.
static java.lang.Object invokeExactMethod(java.lang.Object object, java.lang.String methodName, java.lang.Object arg)
          Invoke a method whose parameter type matches exactly the object type.
static java.lang.Object invokeExactMethod(java.lang.Object object, java.lang.String methodName, java.lang.Object[] args)
          Invoke a method whose parameter types match exactly the object types.
static java.lang.Object invokeExactMethod(java.lang.Object object, java.lang.String methodName, java.lang.Object[] args, java.lang.Class[] parameterTypes)
          Invoke a method whose parameter types match exactly the parameter types given.
static java.lang.Object invokeExactStaticMethod(java.lang.Class objectClass, java.lang.String methodName, java.lang.Object arg)
          Invoke a static method whose parameter type matches exactly the object type.
static java.lang.Object invokeExactStaticMethod(java.lang.Class objectClass, java.lang.String methodName, java.lang.Object[] args)
          Invoke a static method whose parameter types match exactly the object types.
static java.lang.Object invokeExactStaticMethod(java.lang.Class objectClass, java.lang.String methodName, java.lang.Object[] args, java.lang.Class[] parameterTypes)
          Invoke a static method whose parameter types match exactly the parameter types given.
static java.lang.Object invokeMethod(java.lang.Object object, java.lang.String methodName, java.lang.Object arg)
          Invoke a named method whose parameter type matches the object type.
static java.lang.Object invokeMethod(java.lang.Object object, java.lang.String methodName, java.lang.Object[] args)
          Invoke a named method whose parameter type matches the object type.
static java.lang.Object invokeMethod(java.lang.Object object, java.lang.String methodName, java.lang.Object[] args, java.lang.Class[] parameterTypes)
          Invoke a named method whose parameter type matches the object type.
static java.lang.Object invokeStaticMethod(java.lang.Class objectClass, java.lang.String methodName, java.lang.Object arg)
          Invoke a named static method whose parameter type matches the object type.
static java.lang.Object invokeStaticMethod(java.lang.Class objectClass, java.lang.String methodName, java.lang.Object[] args)
          Invoke a named static method whose parameter type matches the object type.
static java.lang.Object invokeStaticMethod(java.lang.Class objectClass, java.lang.String methodName, java.lang.Object[] args, java.lang.Class[] parameterTypes)
          Invoke a named static method whose parameter type matches the object type.
static boolean isAssignmentCompatible(java.lang.Class parameterType, java.lang.Class parameterization)
          Determine whether a type can be used as a parameter in a method invocation.
static void setCacheMethods(boolean cacheMethods)
          Set whether methods should be cached for greater performance or not, default is true.
private static void setMethodAccessible(java.lang.reflect.Method method)
          Try to make the method accessible
static java.lang.Class toNonPrimitiveClass(java.lang.Class clazz)
          Find a non primitive representation for given primitive class.
 
Methods inherited from class java.lang.Object
clone, equals, finalize, getClass, hashCode, notify, notifyAll, toString, wait, wait, wait
 

Field Detail

loggedAccessibleWarning

private static boolean loggedAccessibleWarning
Only log warning about accessibility work around once.

Note that this is broken when this class is deployed via a shared classloader in a container, as the warning message will be emitted only once, not once per webapp. However making the warning appear once per webapp means having a map keyed by context classloader which introduces nasty memory-leak problems. As this warning is really optional we can ignore this problem; only one of the webapps will get the warning in its logs but that should be good enough.


CACHE_METHODS

private static boolean CACHE_METHODS
Indicates whether methods should be cached for improved performance.

Note that when this class is deployed via a shared classloader in a container, this will affect all webapps. However making this configurable per webapp would mean having a map keyed by context classloader which may introduce memory-leak problems.


EMPTY_CLASS_PARAMETERS

private static final java.lang.Class[] EMPTY_CLASS_PARAMETERS
An empty class array


EMPTY_OBJECT_ARRAY

private static final java.lang.Object[] EMPTY_OBJECT_ARRAY
An empty object array


cache

private static final WeakFastHashMap cache
Stores a cache of MethodDescriptor -> Method in a WeakHashMap.

The keys into this map only ever exist as temporary variables within methods of this class, and are never exposed to users of this class. This means that the WeakHashMap is used only as a mechanism for limiting the size of the cache, ie a way to tell the garbage collector that the contents of the cache can be completely garbage-collected whenever it needs the memory. Whether this is a good approach to this problem is doubtful; something like the commons-collections LRUMap may be more appropriate (though of course selecting an appropriate size is an issue).

This static variable is safe even when this code is deployed via a shared classloader because it is keyed via a MethodDescriptor object which has a Class as one of its members and that member is used in the MethodDescriptor.equals method. So two components that load the same class via different classloaders will generate non-equal MethodDescriptor objects and hence end up with different entries in the map.

Constructor Detail

MethodUtils

public MethodUtils()
Method Detail

setCacheMethods

public static void setCacheMethods(boolean cacheMethods)
Set whether methods should be cached for greater performance or not, default is true.

Parameters:
cacheMethods - true if methods should be cached for greater performance, otherwise false

clearCache

public static int clearCache()
Clear the method cache.

Returns:
the number of cached methods cleared

invokeMethod

public static java.lang.Object invokeMethod(java.lang.Object object,
                                            java.lang.String methodName,
                                            java.lang.Object arg)
                                     throws java.lang.NoSuchMethodException,
                                            java.lang.IllegalAccessException,
                                            java.lang.reflect.InvocationTargetException

Invoke a named method whose parameter type matches the object type.

The behaviour of this method is less deterministic than invokeExactMethod(). It loops through all methods with names that match and then executes the first it finds with compatable parameters.

This method supports calls to methods taking primitive parameters via passing in wrapping classes. So, for example, a Boolean class would match a boolean primitive.

This is a convenient wrapper for invokeMethod(Object object,String methodName,Object [] args).

Parameters:
object - invoke method on this object
methodName - get method with this name
arg - use this argument
Returns:
The value returned by the invoked method
Throws:
java.lang.NoSuchMethodException - if there is no such accessible method
java.lang.reflect.InvocationTargetException - wraps an exception thrown by the method invoked
java.lang.IllegalAccessException - if the requested method is not accessible via reflection

invokeMethod

public static java.lang.Object invokeMethod(java.lang.Object object,
                                            java.lang.String methodName,
                                            java.lang.Object[] args)
                                     throws java.lang.NoSuchMethodException,
                                            java.lang.IllegalAccessException,
                                            java.lang.reflect.InvocationTargetException

Invoke a named method whose parameter type matches the object type.

The behaviour of this method is less deterministic than invokeExactMethod(Object object,String methodName,Object [] args). It loops through all methods with names that match and then executes the first it finds with compatable parameters.

This method supports calls to methods taking primitive parameters via passing in wrapping classes. So, for example, a Boolean class would match a boolean primitive.

This is a convenient wrapper for invokeMethod(Object object,String methodName,Object [] args,Class[] parameterTypes).

Parameters:
object - invoke method on this object
methodName - get method with this name
args - use these arguments - treat null as empty array
Returns:
The value returned by the invoked method
Throws:
java.lang.NoSuchMethodException - if there is no such accessible method
java.lang.reflect.InvocationTargetException - wraps an exception thrown by the method invoked
java.lang.IllegalAccessException - if the requested method is not accessible via reflection

invokeMethod

public static java.lang.Object invokeMethod(java.lang.Object object,
                                            java.lang.String methodName,
                                            java.lang.Object[] args,
                                            java.lang.Class[] parameterTypes)
                                     throws java.lang.NoSuchMethodException,
                                            java.lang.IllegalAccessException,
                                            java.lang.reflect.InvocationTargetException

Invoke a named method whose parameter type matches the object type.

The behaviour of this method is less deterministic than invokeExactMethod(Object object,String methodName,Object [] args,Class[] parameterTypes). It loops through all methods with names that match and then executes the first it finds with compatable parameters.

This method supports calls to methods taking primitive parameters via passing in wrapping classes. So, for example, a Boolean class would match a boolean primitive.

Parameters:
object - invoke method on this object
methodName - get method with this name
args - use these arguments - treat null as empty array
parameterTypes - match these parameters - treat null as empty array
Returns:
The value returned by the invoked method
Throws:
java.lang.NoSuchMethodException - if there is no such accessible method
java.lang.reflect.InvocationTargetException - wraps an exception thrown by the method invoked
java.lang.IllegalAccessException - if the requested method is not accessible via reflection

invokeExactMethod

public static java.lang.Object invokeExactMethod(java.lang.Object object,
                                                 java.lang.String methodName,
                                                 java.lang.Object arg)
                                          throws java.lang.NoSuchMethodException,
                                                 java.lang.IllegalAccessException,
                                                 java.lang.reflect.InvocationTargetException

Invoke a method whose parameter type matches exactly the object type.

This is a convenient wrapper for invokeExactMethod(Object object,String methodName,Object [] args).

Parameters:
object - invoke method on this object
methodName - get method with this name
arg - use this argument
Returns:
The value returned by the invoked method
Throws:
java.lang.NoSuchMethodException - if there is no such accessible method
java.lang.reflect.InvocationTargetException - wraps an exception thrown by the method invoked
java.lang.IllegalAccessException - if the requested method is not accessible via reflection

invokeExactMethod

public static java.lang.Object invokeExactMethod(java.lang.Object object,
                                                 java.lang.String methodName,
                                                 java.lang.Object[] args)
                                          throws java.lang.NoSuchMethodException,
                                                 java.lang.IllegalAccessException,
                                                 java.lang.reflect.InvocationTargetException

Invoke a method whose parameter types match exactly the object types.

This uses reflection to invoke the method obtained from a call to getAccessibleMethod().

Parameters:
object - invoke method on this object
methodName - get method with this name
args - use these arguments - treat null as empty array
Returns:
The value returned by the invoked method
Throws:
java.lang.NoSuchMethodException - if there is no such accessible method
java.lang.reflect.InvocationTargetException - wraps an exception thrown by the method invoked
java.lang.IllegalAccessException - if the requested method is not accessible via reflection

invokeExactMethod

public static java.lang.Object invokeExactMethod(java.lang.Object object,
                                                 java.lang.String methodName,
                                                 java.lang.Object[] args,
                                                 java.lang.Class[] parameterTypes)
                                          throws java.lang.NoSuchMethodException,
                                                 java.lang.IllegalAccessException,
                                                 java.lang.reflect.InvocationTargetException

Invoke a method whose parameter types match exactly the parameter types given.

This uses reflection to invoke the method obtained from a call to getAccessibleMethod().

Parameters:
object - invoke method on this object
methodName - get method with this name
args - use these arguments - treat null as empty array
parameterTypes - match these parameters - treat null as empty array
Returns:
The value returned by the invoked method
Throws:
java.lang.NoSuchMethodException - if there is no such accessible method
java.lang.reflect.InvocationTargetException - wraps an exception thrown by the method invoked
java.lang.IllegalAccessException - if the requested method is not accessible via reflection

invokeExactStaticMethod

public static java.lang.Object invokeExactStaticMethod(java.lang.Class objectClass,
                                                       java.lang.String methodName,
                                                       java.lang.Object[] args,
                                                       java.lang.Class[] parameterTypes)
                                                throws java.lang.NoSuchMethodException,
                                                       java.lang.IllegalAccessException,
                                                       java.lang.reflect.InvocationTargetException

Invoke a static method whose parameter types match exactly the parameter types given.

This uses reflection to invoke the method obtained from a call to getAccessibleMethod(Class, String, Class[]).

Parameters:
objectClass - invoke static method on this class
methodName - get method with this name
args - use these arguments - treat null as empty array
parameterTypes - match these parameters - treat null as empty array
Returns:
The value returned by the invoked method
Throws:
java.lang.NoSuchMethodException - if there is no such accessible method
java.lang.reflect.InvocationTargetException - wraps an exception thrown by the method invoked
java.lang.IllegalAccessException - if the requested method is not accessible via reflection

invokeStaticMethod

public static java.lang.Object invokeStaticMethod(java.lang.Class objectClass,
                                                  java.lang.String methodName,
                                                  java.lang.Object arg)
                                           throws java.lang.NoSuchMethodException,
                                                  java.lang.IllegalAccessException,
                                                  java.lang.reflect.InvocationTargetException

Invoke a named static method whose parameter type matches the object type.

The behaviour of this method is less deterministic than invokeExactMethod(Object, String, Object[], Class[]). It loops through all methods with names that match and then executes the first it finds with compatable parameters.

This method supports calls to methods taking primitive parameters via passing in wrapping classes. So, for example, a Boolean class would match a boolean primitive.

This is a convenient wrapper for invokeStaticMethod(Class objectClass,String methodName,Object [] args).

Parameters:
objectClass - invoke static method on this class
methodName - get method with this name
arg - use this argument
Returns:
The value returned by the invoked method
Throws:
java.lang.NoSuchMethodException - if there is no such accessible method
java.lang.reflect.InvocationTargetException - wraps an exception thrown by the method invoked
java.lang.IllegalAccessException - if the requested method is not accessible via reflection

invokeStaticMethod

public static java.lang.Object invokeStaticMethod(java.lang.Class objectClass,
                                                  java.lang.String methodName,
                                                  java.lang.Object[] args)
                                           throws java.lang.NoSuchMethodException,
                                                  java.lang.IllegalAccessException,
                                                  java.lang.reflect.InvocationTargetException

Invoke a named static method whose parameter type matches the object type.

The behaviour of this method is less deterministic than invokeExactMethod(Object object,String methodName,Object [] args). It loops through all methods with names that match and then executes the first it finds with compatable parameters.

This method supports calls to methods taking primitive parameters via passing in wrapping classes. So, for example, a Boolean class would match a boolean primitive.

This is a convenient wrapper for invokeStaticMethod(Class objectClass,String methodName,Object [] args,Class[] parameterTypes).

Parameters:
objectClass - invoke static method on this class
methodName - get method with this name
args - use these arguments - treat null as empty array
Returns:
The value returned by the invoked method
Throws:
java.lang.NoSuchMethodException - if there is no such accessible method
java.lang.reflect.InvocationTargetException - wraps an exception thrown by the method invoked
java.lang.IllegalAccessException - if the requested method is not accessible via reflection

invokeStaticMethod

public static java.lang.Object invokeStaticMethod(java.lang.Class objectClass,
                                                  java.lang.String methodName,
                                                  java.lang.Object[] args,
                                                  java.lang.Class[] parameterTypes)
                                           throws java.lang.NoSuchMethodException,
                                                  java.lang.IllegalAccessException,
                                                  java.lang.reflect.InvocationTargetException

Invoke a named static method whose parameter type matches the object type.

The behaviour of this method is less deterministic than invokeExactStaticMethod(Class objectClass,String methodName,Object [] args,Class[] parameterTypes). It loops through all methods with names that match and then executes the first it finds with compatable parameters.

This method supports calls to methods taking primitive parameters via passing in wrapping classes. So, for example, a Boolean class would match a boolean primitive.

Parameters:
objectClass - invoke static method on this class
methodName - get method with this name
args - use these arguments - treat null as empty array
parameterTypes - match these parameters - treat null as empty array
Returns:
The value returned by the invoked method
Throws:
java.lang.NoSuchMethodException - if there is no such accessible method
java.lang.reflect.InvocationTargetException - wraps an exception thrown by the method invoked
java.lang.IllegalAccessException - if the requested method is not accessible via reflection

invokeExactStaticMethod

public static java.lang.Object invokeExactStaticMethod(java.lang.Class objectClass,
                                                       java.lang.String methodName,
                                                       java.lang.Object arg)
                                                throws java.lang.NoSuchMethodException,
                                                       java.lang.IllegalAccessException,
                                                       java.lang.reflect.InvocationTargetException

Invoke a static method whose parameter type matches exactly the object type.

This is a convenient wrapper for invokeExactStaticMethod(Class objectClass,String methodName,Object [] args).

Parameters:
objectClass - invoke static method on this class
methodName - get method with this name
arg - use this argument
Returns:
The value returned by the invoked method
Throws:
java.lang.NoSuchMethodException - if there is no such accessible method
java.lang.reflect.InvocationTargetException - wraps an exception thrown by the method invoked
java.lang.IllegalAccessException - if the requested method is not accessible via reflection

invokeExactStaticMethod

public static java.lang.Object invokeExactStaticMethod(java.lang.Class objectClass,
                                                       java.lang.String methodName,
                                                       java.lang.Object[] args)
                                                throws java.lang.NoSuchMethodException,
                                                       java.lang.IllegalAccessException,
                                                       java.lang.reflect.InvocationTargetException

Invoke a static method whose parameter types match exactly the object types.

This uses reflection to invoke the method obtained from a call to getAccessibleMethod(Class, String, Class[]).

Parameters:
objectClass - invoke static method on this class
methodName - get method with this name
args - use these arguments - treat null as empty array
Returns:
The value returned by the invoked method
Throws:
java.lang.NoSuchMethodException - if there is no such accessible method
java.lang.reflect.InvocationTargetException - wraps an exception thrown by the method invoked
java.lang.IllegalAccessException - if the requested method is not accessible via reflection

getAccessibleMethod

public static java.lang.reflect.Method getAccessibleMethod(java.lang.Class clazz,
                                                           java.lang.String methodName,
                                                           java.lang.Class parameterType)

Return an accessible method (that is, one that can be invoked via reflection) with given name and a single parameter. If no such method can be found, return null. Basically, a convenience wrapper that constructs a Class array for you.

Parameters:
clazz - get method from this class
methodName - get method with this name
parameterType - taking this type of parameter
Returns:
The accessible method

getAccessibleMethod

public static java.lang.reflect.Method getAccessibleMethod(java.lang.Class clazz,
                                                           java.lang.String methodName,
                                                           java.lang.Class[] parameterTypes)

Return an accessible method (that is, one that can be invoked via reflection) with given name and parameters. If no such method can be found, return null. This is just a convenient wrapper for getAccessibleMethod(Method method).

Parameters:
clazz - get method from this class
methodName - get method with this name
parameterTypes - with these parameters types
Returns:
The accessible method

getAccessibleMethod

public static java.lang.reflect.Method getAccessibleMethod(java.lang.reflect.Method method)

Return an accessible method (that is, one that can be invoked via reflection) that implements the specified Method. If no such method can be found, return null.

Parameters:
method - The method that we wish to call
Returns:
The accessible method

getAccessibleMethod

public static java.lang.reflect.Method getAccessibleMethod(java.lang.Class clazz,
                                                           java.lang.reflect.Method method)

Return an accessible method (that is, one that can be invoked via reflection) that implements the specified Method. If no such method can be found, return null.

Parameters:
clazz - The class of the object
method - The method that we wish to call
Returns:
The accessible method

getAccessibleMethodFromSuperclass

private static java.lang.reflect.Method getAccessibleMethodFromSuperclass(java.lang.Class clazz,
                                                                          java.lang.String methodName,
                                                                          java.lang.Class[] parameterTypes)

Return an accessible method (that is, one that can be invoked via reflection) by scanning through the superclasses. If no such method can be found, return null.

Parameters:
clazz - Class to be checked
methodName - Method name of the method we wish to call
parameterTypes - The parameter type signatures

getAccessibleMethodFromInterfaceNest

private static java.lang.reflect.Method getAccessibleMethodFromInterfaceNest(java.lang.Class clazz,
                                                                             java.lang.String methodName,
                                                                             java.lang.Class[] parameterTypes)

Return an accessible method (that is, one that can be invoked via reflection) that implements the specified method, by scanning through all implemented interfaces and subinterfaces. If no such method can be found, return null.

There isn't any good reason why this method must be private. It is because there doesn't seem any reason why other classes should call this rather than the higher level methods.

Parameters:
clazz - Parent class for the interfaces to be checked
methodName - Method name of the method we wish to call
parameterTypes - The parameter type signatures

getMatchingAccessibleMethod

public static java.lang.reflect.Method getMatchingAccessibleMethod(java.lang.Class clazz,
                                                                   java.lang.String methodName,
                                                                   java.lang.Class[] parameterTypes)

Find an accessible method that matches the given name and has compatible parameters. Compatible parameters mean that every method parameter is assignable from the given parameters. In other words, it finds a method with the given name that will take the parameters given.

This method is slightly undeterminstic since it loops through methods names and return the first matching method.

This method is used by invokeMethod(Object object,String methodName,Object [] args,Class[] parameterTypes).

This method can match primitive parameter by passing in wrapper classes. For example, a Boolean will match a primitive boolean parameter.

Parameters:
clazz - find method in this class
methodName - find method with this name
parameterTypes - find method with compatible parameters
Returns:
The accessible method

setMethodAccessible

private static void setMethodAccessible(java.lang.reflect.Method method)
Try to make the method accessible

Parameters:
method - The source arguments

getTotalTransformationCost

private static float getTotalTransformationCost(java.lang.Class[] srcArgs,
                                                java.lang.Class[] destArgs)
Returns the sum of the object transformation cost for each class in the source argument list.

Parameters:
srcArgs - The source arguments
destArgs - The destination arguments
Returns:
The total transformation cost

getObjectTransformationCost

private static float getObjectTransformationCost(java.lang.Class srcClass,
                                                 java.lang.Class destClass)
Gets the number of steps required needed to turn the source class into the destination class. This represents the number of steps in the object hierarchy graph.

Parameters:
srcClass - The source class
destClass - The destination class
Returns:
The cost of transforming an object

isAssignmentCompatible

public static final boolean isAssignmentCompatible(java.lang.Class parameterType,
                                                   java.lang.Class parameterization)

Determine whether a type can be used as a parameter in a method invocation. This method handles primitive conversions correctly.

In order words, it will match a Boolean to a boolean, a Long to a long, a Float to a float, a Integer to a int, and a Double to a double. Now logic widening matches are allowed. For example, a Long will not match a int.

Parameters:
parameterType - the type of parameter accepted by the method
parameterization - the type of parameter being tested
Returns:
true if the assignement is compatible.

getPrimitiveWrapper

public static java.lang.Class getPrimitiveWrapper(java.lang.Class primitiveType)
Gets the wrapper object class for the given primitive type class. For example, passing boolean.class returns Boolean.class

Parameters:
primitiveType - the primitive type class for which a match is to be found
Returns:
the wrapper type associated with the given primitive or null if no match is found

getPrimitiveType

public static java.lang.Class getPrimitiveType(java.lang.Class wrapperType)
Gets the class for the primitive type corresponding to the primitive wrapper class given. For example, an instance of Boolean.class returns a boolean.class.

Parameters:
wrapperType - the
Returns:
the primitive type class corresponding to the given wrapper class, null if no match is found

toNonPrimitiveClass

public static java.lang.Class toNonPrimitiveClass(java.lang.Class clazz)
Find a non primitive representation for given primitive class.

Parameters:
clazz - the class to find a representation for, not null
Returns:
the original class if it not a primitive. Otherwise the wrapper class. Not null

getCachedMethod

private static java.lang.reflect.Method getCachedMethod(MethodUtils.MethodDescriptor md)
Return the method from the cache, if present.

Parameters:
md - The method descriptor
Returns:
The cached method

cacheMethod

private static void cacheMethod(MethodUtils.MethodDescriptor md,
                                java.lang.reflect.Method method)
Add a method to the cache.

Parameters:
md - The method descriptor
method - The method to cache


Copyright (c) 2000-2008 - Apache Software Foundation