From 554fd8c5195424bdbcabf5de30fdc183aba391bd Mon Sep 17 00:00:00 2001 From: upstream source tree Date: Sun, 15 Mar 2015 20:14:05 -0400 Subject: obtained gcc-4.6.4.tar.bz2 from upstream website; verified gcc-4.6.4.tar.bz2.sig; imported gcc-4.6.4 source tree from verified upstream tarball. downloading a git-generated archive based on the 'upstream' tag should provide you with a source tree that is binary identical to the one extracted from the above tarball. if you have obtained the source via the command 'git clone', however, do note that line-endings of files in your working directory might differ from line-endings of the respective files in the upstream repository. --- libjava/classpath/java/beans/Expression.java | 138 +++++++++++++++++++++++++++ 1 file changed, 138 insertions(+) create mode 100644 libjava/classpath/java/beans/Expression.java (limited to 'libjava/classpath/java/beans/Expression.java') diff --git a/libjava/classpath/java/beans/Expression.java b/libjava/classpath/java/beans/Expression.java new file mode 100644 index 000000000..d07c28b4a --- /dev/null +++ b/libjava/classpath/java/beans/Expression.java @@ -0,0 +1,138 @@ +/* java.beans.Expression + Copyright (C) 2004, 2005 Free Software Foundation, Inc. + +This file is part of GNU Classpath. + +GNU Classpath is free software; you can redistribute it and/or modify +it under the terms of the GNU General Public License as published by +the Free Software Foundation; either version 2, or (at your option) +any later version. + +GNU Classpath is distributed in the hope that it will be useful, but +WITHOUT ANY WARRANTY; without even the implied warranty of +MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU +General Public License for more details. + +You should have received a copy of the GNU General Public License +along with GNU Classpath; see the file COPYING. If not, write to the +Free Software Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA +02110-1301 USA. + +Linking this library statically or dynamically with other modules is +making a combined work based on this library. Thus, the terms and +conditions of the GNU General Public License cover the whole +combination. + +As a special exception, the copyright holders of this library give you +permission to link this library with independent modules to produce an +executable, regardless of the license terms of these independent +modules, and to copy and distribute the resulting executable under +terms of your choice, provided that you also meet, for each linked +independent module, the terms and conditions of the license of that +module. An independent module is a module which is not derived from +or based on this library. If you modify this library, you may extend +this exception to your version of the library, but you are not +obligated to do so. If you do not wish to do so, delete this +exception statement from your version. */ + +package java.beans; + +/** + *

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.

+ * + * @author Robert Schuster (robertschuster@fsfe.org) + * @since 1.4 + */ +public class Expression extends Statement +{ + // This is a placeholder to indicate that value hasn't been set + // yet; + private static final Object UNSET = new Object(); + + // The value to return. This is equal to unset until getValue is called. + private Object value; + + /** + * 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. + * + * @param value + * The value to return. + * @param target + * The object to invoke the method on. + * @param methodName + * The object method to invoke. + * @param arguments + * An array of arguments to pass to the method. + */ + public Expression(Object value, Object target, String methodName, + Object[] arguments) + { + super(target, methodName, arguments); + this.value = value; + } + + /** + * Constructor Constructs an Expression representing the invocation of + * object.methodName(arg[0], arg[1], ...); + * + * @param target + * The object to invoke the method on. + * @param methodName + * The object method to invoke. + * @param arguments + * An array of arguments to pass to the method. + */ + public Expression(Object target, String methodName, Object[] arguments) + { + super(target, methodName, arguments); + this.value = UNSET; + } + + /** + * 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. + * + * @return the result of executing the method. + * @exception Exception + * if an error occurs + */ + public Object getValue() throws Exception + { + if (value == UNSET) + value = doExecute(); + return value; + } + + /** + * Set the cached value to be returned by getValue() + * + * @param value + * the value to cache and return. + */ + public void setValue(Object value) + { + this.value = value; + } + + /** + * Return a string representation of this expression. + */ + public String toString() + { + String result = super.toString(); + if (value != UNSET) + return value.getClass().getName() + "=" + result; + return result; + } +} -- cgit v1.2.3