de.odysseus.el
Class ObjectValueExpression

java.lang.Object
  extended by javax.el.Expression
      extended by javax.el.ValueExpression
          extended by de.odysseus.el.ObjectValueExpression
All Implemented Interfaces:
java.io.Serializable

public final class ObjectValueExpression
extends ValueExpression

Object wrapper expression.

Author:
Christoph Beck
See Also:
Serialized Form

Constructor Summary
ObjectValueExpression(TypeConverter converter, java.lang.Object object, java.lang.Class<?> type)
          Wrap an object into a value expression.
 
Method Summary
 boolean equals(java.lang.Object obj)
          Two object value expressions are equal if and only if their wrapped objects are equal.
 java.lang.Class<?> getExpectedType()
          Returns the type the result of the expression will be coerced to after evaluation.
 java.lang.String getExpressionString()
          Answer null.
 java.lang.Class<?> getType(ELContext context)
          Answer null.
 java.lang.Object getValue(ELContext context)
          Answer the wrapped object, coerced to the expected type.
 int hashCode()
          Returns the hash code for this Expression.
 boolean isLiteralText()
          Answer false.
 boolean isReadOnly(ELContext context)
          Answer true.
 void setValue(ELContext context, java.lang.Object value)
          Throw an exception.
 java.lang.String toString()
           
 
Methods inherited from class javax.el.ValueExpression
getValueReference
 
Methods inherited from class java.lang.Object
clone, finalize, getClass, notify, notifyAll, wait, wait, wait
 

Constructor Detail

ObjectValueExpression

public ObjectValueExpression(TypeConverter converter,
                             java.lang.Object object,
                             java.lang.Class<?> type)
Wrap an object into a value expression.

Parameters:
converter - type converter
object - the object to wrap
type - the expected type this object will be coerced in getValue(ELContext).
Method Detail

equals

public boolean equals(java.lang.Object obj)
Two object value expressions are equal if and only if their wrapped objects are equal.

Specified by:
equals in class Expression
Parameters:
obj - the Object to test for equality.
Returns:
true if obj equals this Expression; false otherwise.

hashCode

public int hashCode()
Description copied from class: Expression
Returns the hash code for this Expression. See the note in the Expression.equals(Object) method on how two expressions can be equal if their expression Strings are different. Recall that if two objects are equal according to the equals(Object) method, then calling the hashCode method on each of the two objects must produce the same integer result. Implementations must take special note and implement hashCode correctly.

Specified by:
hashCode in class Expression
Returns:
The hash code for this Expression.
See Also:
Expression.equals(Object), Hashtable, Object.hashCode()

getValue

public java.lang.Object getValue(ELContext context)
Answer the wrapped object, coerced to the expected type.

Specified by:
getValue in class ValueExpression
Parameters:
context - The context of this evaluation.
Returns:
The result of the expression evaluation.

getExpressionString

public java.lang.String getExpressionString()
Answer null.

Specified by:
getExpressionString in class Expression
Returns:
The original expression String.

isLiteralText

public boolean isLiteralText()
Answer false.

Specified by:
isLiteralText in class Expression
Returns:
true if this expression was created from only literal text; false otherwise.

getType

public java.lang.Class<?> getType(ELContext context)
Answer null.

Specified by:
getType in class ValueExpression
Parameters:
context - The context of this evaluation.
Returns:
the most general acceptable type; otherwise undefined.

isReadOnly

public boolean isReadOnly(ELContext context)
Answer true.

Specified by:
isReadOnly in class ValueExpression
Parameters:
context - The context of this evaluation.
Returns:
true if the expression is read-only or false if not.

setValue

public void setValue(ELContext context,
                     java.lang.Object value)
Throw an exception.

Specified by:
setValue in class ValueExpression
Parameters:
context - The context of this evaluation.
value - The new value to be set.

toString

public java.lang.String toString()
Overrides:
toString in class java.lang.Object

getExpectedType

public java.lang.Class<?> getExpectedType()
Description copied from class: ValueExpression
Returns the type the result of the expression will be coerced to after evaluation.

Specified by:
getExpectedType in class ValueExpression
Returns:
the expectedType passed to the ExpressionFactory.createValueExpression method that created this ValueExpression.

Copyright © 2006-2009 Odysseus Software GmbH.