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src/java.desktop/share/classes/java/beans/Expression.java
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*** 24,43 ****
*/
package java.beans;
/**
! * An <code>Expression</code> object represents a primitive expression
* in which a single method is applied to a target and a set of
! * arguments to return a result - as in <code>"a.getFoo()"</code>.
* <p>
* In addition to the properties of the super class, the
! * <code>Expression</code> object provides a <em>value</em> which
* is the object returned when this expression is evaluated.
* The return value is typically not provided by the caller and
* is instead computed by dynamically finding the method and invoking
! * it when the first call to <code>getValue</code> is made.
*
* @see #getValue
* @see #setValue
*
* @since 1.4
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*/
package java.beans;
/**
! * An {@code Expression} object represents a primitive expression
* in which a single method is applied to a target and a set of
! * arguments to return a result - as in {@code "a.getFoo()"}.
* <p>
* In addition to the properties of the super class, the
! * {@code Expression} object provides a <em>value</em> which
* is the object returned when this expression is evaluated.
* The return value is typically not provided by the caller and
* is instead computed by dynamically finding the method and invoking
! * it when the first call to {@code getValue} is made.
*
* @see #getValue
* @see #setValue
*
* @since 1.4
*** 125,147 ****
* If the value property of this instance is not already set,
* this method dynamically finds the method with the specified
* methodName on this target with these arguments and calls it.
* The result of the method invocation is first copied
* into the value property of this expression and then returned
! * as the result of <code>getValue</code>. If the value property
! * was already set, either by a call to <code>setValue</code>
! * or a previous call to <code>getValue</code> then the value
* property is returned without either looking up or calling the method.
* <p>
! * The value property of an <code>Expression</code> is set to
! * a unique private (non-<code>null</code>) value by default and
* this value is used as an internal indication that the method
! * has not yet been called. A return value of <code>null</code>
* replaces this default value in the same way that any other value
* would, ensuring that expressions are never evaluated more than once.
* <p>
! * See the <code>execute</code> method for details on how
* methods are chosen using the dynamic types of the target
* and arguments.
*
* @see Statement#execute
* @see #setValue
--- 125,147 ----
* If the value property of this instance is not already set,
* this method dynamically finds the method with the specified
* methodName on this target with these arguments and calls it.
* The result of the method invocation is first copied
* into the value property of this expression and then returned
! * as the result of {@code getValue}. If the value property
! * was already set, either by a call to {@code setValue}
! * or a previous call to {@code getValue} then the value
* property is returned without either looking up or calling the method.
* <p>
! * The value property of an {@code Expression} is set to
! * a unique private (non-{@code null}) value by default and
* this value is used as an internal indication that the method
! * has not yet been called. A return value of {@code null}
* replaces this default value in the same way that any other value
* would, ensuring that expressions are never evaluated more than once.
* <p>
! * See the {@code execute} method for details on how
* methods are chosen using the dynamic types of the target
* and arguments.
*
* @see Statement#execute
* @see #setValue
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}
return value;
}
/**
! * Sets the value of this expression to <code>value</code>.
* This value will be returned by the getValue method
* without calling the method associated with this
* expression.
*
* @param value The value of this expression.
--- 156,166 ----
}
return value;
}
/**
! * Sets the value of this expression to {@code value}.
* This value will be returned by the getValue method
* without calling the method associated with this
* expression.
*
* @param value The value of this expression.
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