java.beans
Class Expression

java.lang.Object
  extended by java.beans.Statement
      extended by java.beans.Expression

public class Expression
extends Statement

An Expression captures the execution of an object method that returns a value.

It stores an object, the method to call, and the arguments to pass to the method.

While this class can generally be used to describe method calls it is part of the XML serialization API.

Since:
1.4

Constructor Summary
Expression(Object value, Object target, String methodName, Object[] arguments)
          Constructor Constructs an Expression representing the invocation of object.methodName(arg[0], arg[1], ...); However, it will never be executed.
Expression(Object target, String methodName, Object[] arguments)
          Constructor Constructs an Expression representing the invocation of object.methodName(arg[0], arg[1],
 
Method Summary
 Object getValue()
          Return the result of executing the method.
 void setValue(Object value)
          Set the cached value to be returned by getValue()
 String toString()
          Return a string representation of this expression.
 
Methods inherited from class java.beans.Statement
execute, getArguments, getMethodName, getTarget
 
Methods inherited from class java.lang.Object
clone, equals, finalize, getClass, hashCode, notify, notifyAll, wait, wait, wait
 

Constructor Detail

Expression

public Expression(Object value,
                  Object target,
                  String methodName,
                  Object[] arguments)
Constructor Constructs an Expression representing the invocation of object.methodName(arg[0], arg[1], ...); However, it will never be executed. Instead, value will always be returned.

Parameters:
value - The value to return.
target - The object to invoke the method on.
methodName - The object method to invoke.
arguments - An array of arguments to pass to the method.

Expression

public Expression(Object target,
                  String methodName,
                  Object[] arguments)
Constructor Constructs an Expression representing the invocation of object.methodName(arg[0], arg[1], ...);

Parameters:
target - The object to invoke the method on.
methodName - The object method to invoke.
arguments - An array of arguments to pass to the method.
Method Detail

getValue

public Object getValue()
                throws Exception
Return the result of executing the method. If the cached value has not yet been set, the method is executed in the same way as Statement.execute(), except that the value is cached, and then returned. If the value has been set, it is returned without executing the method again.

Returns:
the result of executing the method.
Throws:
Exception - if an error occurs

setValue

public void setValue(Object value)
Set the cached value to be returned by getValue()

Parameters:
value - the value to cache and return.

toString

public String toString()
Return a string representation of this expression.

Overrides:
toString in class Statement
Returns:
A string representation of this Statement.
See Also:
Object.getClass(), Object.hashCode(), Class.getName(), Integer.toHexString(int)