Class MethodMap
- java.lang.Object
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- org.apache.velocity.util.introspection.MethodMap
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public class MethodMap extends java.lang.Object
- Version:
- $Id$
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Nested Class Summary
Nested Classes Modifier and Type Class Description static class
MethodMap.AmbiguousException
Simple distinguishable exception, used when we run across ambiguous overloading.private class
MethodMap.Match
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Field Summary
Fields Modifier and Type Field Description (package private) TypeConversionHandler
conversionHandler
private static int
EQUIVALENT
private static int
EXPLICITLY_CONVERTIBLE
private static int
IMPLCITLY_CONVERTIBLE
private static int
INCOMPARABLE
private static int
LESS_SPECIFIC
(package private) java.util.Map<java.lang.String,java.util.List<java.lang.reflect.Method>>
methodByNameMap
Keep track of all methods with the same name.private static int
MORE_SPECIFIC
private static int
NOT_CONVERTIBLE
private static int
STRICTLY_CONVERTIBLE
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Constructor Summary
Constructors Constructor Description MethodMap()
Default constructorMethodMap(TypeConversionHandler conversionHandler)
Constructor with provided conversion handler
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Method Summary
All Methods Static Methods Instance Methods Concrete Methods Modifier and Type Method Description void
add(java.lang.reflect.Method method)
Add a method to a list of methods by name.private int
compare(java.lang.reflect.Type[] t1, java.lang.reflect.Type[] t2)
Determines which method signature (represented by a class array) is more specific.java.lang.reflect.Method
find(java.lang.String methodName, java.lang.Object[] args)
Find a method.java.util.List<java.lang.reflect.Method>
get(java.lang.String key)
Return a list of methods with the same name.private int
getApplicability(java.lang.reflect.Method method, java.lang.Class<?>[] classes)
Returns the applicability of the supplied method against actual argument types.private java.lang.reflect.Method
getBestMatch(java.util.List<java.lang.reflect.Method> methods, java.lang.Class<?>[] args)
private boolean
isConvertible(java.lang.reflect.Type formal, java.lang.Class<?> actual, boolean possibleVarArg)
Returns true ifactual
is convertible toformal
by implicit Java method call conversionsprivate boolean
isExplicitlyConvertible(java.lang.reflect.Type formal, java.lang.Class<?> actual, boolean possibleVarArg)
Returns true ifactual
is convertible toformal
using an explicit converterprivate static boolean
isStrictConvertible(java.lang.reflect.Type formal, java.lang.Class<?> actual, boolean possibleVarArg)
Returns true ifactual
is strictly convertible toformal
(aka without implicit boxing/unboxing)private static boolean
onlyNullOrObjects(java.lang.Class<?>[] args)
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Field Detail
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INCOMPARABLE
private static final int INCOMPARABLE
- See Also:
- Constant Field Values
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MORE_SPECIFIC
private static final int MORE_SPECIFIC
- See Also:
- Constant Field Values
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EQUIVALENT
private static final int EQUIVALENT
- See Also:
- Constant Field Values
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LESS_SPECIFIC
private static final int LESS_SPECIFIC
- See Also:
- Constant Field Values
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NOT_CONVERTIBLE
private static final int NOT_CONVERTIBLE
- See Also:
- Constant Field Values
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EXPLICITLY_CONVERTIBLE
private static final int EXPLICITLY_CONVERTIBLE
- See Also:
- Constant Field Values
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IMPLCITLY_CONVERTIBLE
private static final int IMPLCITLY_CONVERTIBLE
- See Also:
- Constant Field Values
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STRICTLY_CONVERTIBLE
private static final int STRICTLY_CONVERTIBLE
- See Also:
- Constant Field Values
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conversionHandler
TypeConversionHandler conversionHandler
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methodByNameMap
java.util.Map<java.lang.String,java.util.List<java.lang.reflect.Method>> methodByNameMap
Keep track of all methods with the same name.
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Constructor Detail
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MethodMap
public MethodMap()
Default constructor
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MethodMap
public MethodMap(TypeConversionHandler conversionHandler)
Constructor with provided conversion handler- Parameters:
conversionHandler
- conversion handler- Since:
- 2.0
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Method Detail
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add
public void add(java.lang.reflect.Method method)
Add a method to a list of methods by name. For a particular class we are keeping track of all the methods with the same name.- Parameters:
method
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get
public java.util.List<java.lang.reflect.Method> get(java.lang.String key)
Return a list of methods with the same name.- Parameters:
key
-- Returns:
- List list of methods
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find
public java.lang.reflect.Method find(java.lang.String methodName, java.lang.Object[] args) throws MethodMap.AmbiguousException
Find a method. Attempts to find the most specific applicable method using the algorithm described in the JLS section 15.12.2 (with the exception that it can't distinguish a primitive type argument from an object type argument, since in reflection primitive type arguments are represented by their object counterparts, so for an argument of type (say) java.lang.Integer, it will not be able to decide between a method that takes int and a method that takes java.lang.Integer as a parameter.
This turns out to be a relatively rare case where this is needed - however, functionality like this is needed.
- Parameters:
methodName
- name of methodargs
- the actual arguments with which the method is called- Returns:
- the most specific applicable method, or null if no method is applicable.
- Throws:
MethodMap.AmbiguousException
- if there is more than one maximally specific applicable method
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onlyNullOrObjects
private static boolean onlyNullOrObjects(java.lang.Class<?>[] args)
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getBestMatch
private java.lang.reflect.Method getBestMatch(java.util.List<java.lang.reflect.Method> methods, java.lang.Class<?>[] args)
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compare
private int compare(java.lang.reflect.Type[] t1, java.lang.reflect.Type[] t2)
Determines which method signature (represented by a class array) is more specific. This defines a partial ordering on the method signatures.- Parameters:
t1
- first signature to comparet2
- second signature to compare- Returns:
- MORE_SPECIFIC if c1 is more specific than c2, LESS_SPECIFIC if c1 is less specific than c2, INCOMPARABLE if they are incomparable.
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getApplicability
private int getApplicability(java.lang.reflect.Method method, java.lang.Class<?>[] classes)
Returns the applicability of the supplied method against actual argument types.- Parameters:
method
- method that will be calledclasses
- arguments to method- Returns:
- the level of applicability: 0 = not applicable 1 = explicitly applicable (i.e. using stock or custom conversion handlers) 2 = implicitly applicable (i.e. using JAva implicit boxing/unboxing and primitive types widening) 3 = strictly applicable
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isConvertible
private boolean isConvertible(java.lang.reflect.Type formal, java.lang.Class<?> actual, boolean possibleVarArg)
Returns true ifactual
is convertible toformal
by implicit Java method call conversions- Parameters:
formal
-actual
-possibleVarArg
-- Returns:
- convertible
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isStrictConvertible
private static boolean isStrictConvertible(java.lang.reflect.Type formal, java.lang.Class<?> actual, boolean possibleVarArg)
Returns true ifactual
is strictly convertible toformal
(aka without implicit boxing/unboxing)- Parameters:
formal
-actual
-possibleVarArg
-- Returns:
- convertible
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isExplicitlyConvertible
private boolean isExplicitlyConvertible(java.lang.reflect.Type formal, java.lang.Class<?> actual, boolean possibleVarArg)
Returns true ifactual
is convertible toformal
using an explicit converter- Parameters:
formal
-actual
-possibleVarArg
-- Returns:
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