Package de.odysseus.el

Class TreeMethodExpression

java.lang.Object

javax.el.Expression

javax.el.MethodExpression

de.odysseus.el.TreeMethodExpression

All Implemented Interfaces:

java.io.Serializable

public final class TreeMethodExpression
extends javax.el.MethodExpression

A method expression is ready to be evaluated (by calling either invoke(ELContext, Object[]) or getMethodInfo(ELContext)). Instances of this class are usually created using an ExpressionFactoryImpl.

See Also:

Serialized Form

Field Summary

Fields

Modifier and Type	Field	Description
private Bindings	bindings
private TreeBuilder	builder
private boolean	deferred
private java.lang.String	expr
private ExpressionNode	node
private static long	serialVersionUID
private java.lang.String	structure
private java.lang.Class<?>	type
private java.lang.Class<?>[]	types

Constructor Summary

Constructors

Constructor	Description
TreeMethodExpression(TreeStore store, javax.el.FunctionMapper functions, javax.el.VariableMapper variables, TypeConverter converter, java.lang.String expr, java.lang.Class<?> returnType, java.lang.Class<?>[] paramTypes)	Create a new method expression.

Method Summary

Modifier and Type	Method	Description
void	dump(java.io.PrintWriter writer)	Print the parse tree.
boolean	equals(java.lang.Object obj)	Expressions are compared using the concept of a structural id: variable and function names are anonymized such that two expressions with same tree structure will also have the same structural id and vice versa.
java.lang.String	getExpressionString()
javax.el.MethodInfo	getMethodInfo(javax.el.ELContext context)	Evaluates the expression and answers information about the method
private java.lang.String	getStructuralId()
int	hashCode()
java.lang.Object	invoke(javax.el.ELContext context, java.lang.Object[] paramValues)	Evaluates the expression and invokes the method.
boolean	isDeferred()	Answer true if this is a deferred expression (starting with #{)
boolean	isLiteralText()
boolean	isParmetersProvided()
private void	readObject(java.io.ObjectInputStream in)
java.lang.String	toString()

Methods inherited from class javax.el.MethodExpression

isParametersProvided

Methods inherited from class java.lang.Object

clone, finalize, getClass, notify, notifyAll, wait, wait, wait

Field Detail

serialVersionUID

private static final long serialVersionUID

See Also:

Constant Field Values

builder

private final TreeBuilder builder

bindings

private final Bindings bindings

expr

private final java.lang.String expr

type

private final java.lang.Class<?> type

types

private final java.lang.Class<?>[] types

deferred

private final boolean deferred

node

private transient ExpressionNode node

structure

private java.lang.String structure

Constructor Detail

TreeMethodExpression

public TreeMethodExpression(TreeStore store,
                            javax.el.FunctionMapper functions,
                            javax.el.VariableMapper variables,
                            TypeConverter converter,
                            java.lang.String expr,
                            java.lang.Class<?> returnType,
                            java.lang.Class<?>[] paramTypes)

Create a new method expression. The expression must be an lvalue expression or literal text. The expected return type may be null, meaning "don't care". If it is an lvalue expression, the parameter types must not be null. If it is literal text, the expected return type must not be void.

Parameters:

store - used to get the parse tree from.

functions - the function mapper used to bind functions

variables - the variable mapper used to bind variables

expr - the expression string

returnType - the expected return type (may be null)

paramTypes - the expected parameter types (must not be null for lvalues)

Method Detail

getStructuralId

private java.lang.String getStructuralId()

getMethodInfo

public javax.el.MethodInfo getMethodInfo(javax.el.ELContext context)
                                  throws javax.el.ELException

Evaluates the expression and answers information about the method

Specified by:

getMethodInfo in class javax.el.MethodExpression

Parameters:

context - used to resolve properties (base.property and base[property])

Returns:

method information or null for literal expressions

Throws:

javax.el.ELException - if evaluation fails (e.g. suitable method not found)

getExpressionString

public java.lang.String getExpressionString()

Specified by:

getExpressionString in class javax.el.Expression

invoke

public java.lang.Object invoke(javax.el.ELContext context,
                               java.lang.Object[] paramValues)
                        throws javax.el.ELException

Evaluates the expression and invokes the method.

Specified by:

invoke in class javax.el.MethodExpression

Parameters:

context - used to resolve properties (base.property and base[property])

paramValues -

Returns:

method result or null if this is a literal text expression

Throws:

javax.el.ELException - if evaluation fails (e.g. suitable method not found)

isLiteralText

public boolean isLiteralText()

Specified by:

isLiteralText in class javax.el.Expression

Returns:

true if this is a literal text expression

isParmetersProvided

public boolean isParmetersProvided()

Overrides:

isParmetersProvided in class javax.el.MethodExpression

Returns:

true if this is a method invocation expression

isDeferred

public boolean isDeferred()

Answer true if this is a deferred expression (starting with #{)

equals

public boolean equals(java.lang.Object obj)

Expressions are compared using the concept of a structural id: variable and function names are anonymized such that two expressions with same tree structure will also have the same structural id and vice versa. Two method expressions are equal if

1. their builders are equal
2. their structural id's are equal
3. their bindings are equal
4. their expected types match
5. their parameter types are equal

Specified by:

equals in class javax.el.Expression

hashCode

public int hashCode()

Specified by:

hashCode in class javax.el.Expression

toString

public java.lang.String toString()

Overrides:

toString in class java.lang.Object

dump

public void dump(java.io.PrintWriter writer)

Print the parse tree.

Parameters:

writer -

readObject

private void readObject(java.io.ObjectInputStream in)
                 throws java.io.IOException,
                        java.lang.ClassNotFoundException

Throws:

java.io.IOException

java.lang.ClassNotFoundException