1/* 2 * Copyright (c) 2005, 2013, Oracle and/or its affiliates. All rights reserved. 3 * DO NOT ALTER OR REMOVE COPYRIGHT NOTICES OR THIS FILE HEADER. 4 * 5 * This code is free software; you can redistribute it and/or modify it 6 * under the terms of the GNU General Public License version 2 only, as 7 * published by the Free Software Foundation. Oracle designates this 8 * particular file as subject to the "Classpath" exception as provided 9 * by Oracle in the LICENSE file that accompanied this code. 10 * 11 * This code is distributed in the hope that it will be useful, but WITHOUT 12 * ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or 13 * FITNESS FOR A PARTICULAR PURPOSE. See the GNU General Public License 14 * version 2 for more details (a copy is included in the LICENSE file that 15 * accompanied this code). 16 * 17 * You should have received a copy of the GNU General Public License version 18 * 2 along with this work; if not, write to the Free Software Foundation, 19 * Inc., 51 Franklin St, Fifth Floor, Boston, MA 02110-1301 USA. 20 * 21 * Please contact Oracle, 500 Oracle Parkway, Redwood Shores, CA 94065 USA 22 * or visit www.oracle.com if you need additional information or have any 23 * questions. 24 */ 25 26package javax.script; 27 28import java.util.Map; 29 30/** 31 * Extended by classes that store results of compilations. State 32 * might be stored in the form of Java classes, Java class files or scripting 33 * language opcodes. The script may be executed repeatedly 34 * without reparsing. 35 * <br><br> 36 * Each <code>CompiledScript</code> is associated with a <code>ScriptEngine</code> -- A call to an <code>eval</code> 37 * method of the <code>CompiledScript</code> causes the execution of the script by the 38 * <code>ScriptEngine</code>. Changes in the state of the <code>ScriptEngine</code> caused by execution 39 * of the <code>CompiledScript</code> may visible during subsequent executions of scripts by the engine. 40 * 41 * @author Mike Grogan 42 * @since 1.6 43 */ 44public abstract class CompiledScript { 45 46 /** 47 * Executes the program stored in this <code>CompiledScript</code> object. 48 * 49 * @param context A <code>ScriptContext</code> that is used in the same way as 50 * the <code>ScriptContext</code> passed to the <code>eval</code> methods of 51 * <code>ScriptEngine</code>. 52 * 53 * @return The value returned by the script execution, if any. Should return <code>null</code> 54 * if no value is returned by the script execution. 55 * 56 * @throws ScriptException if an error occurs. 57 * @throws NullPointerException if context is null. 58 */ 59 60 public abstract Object eval(ScriptContext context) throws ScriptException; 61 62 /** 63 * Executes the program stored in the <code>CompiledScript</code> object using 64 * the supplied <code>Bindings</code> of attributes as the <code>ENGINE_SCOPE</code> of the 65 * associated <code>ScriptEngine</code> during script execution. If bindings is null, 66 * then the effect of calling this method is same as that of eval(getEngine().getContext()). 67 * <p>. 68 * The <code>GLOBAL_SCOPE</code> <code>Bindings</code>, <code>Reader</code> and <code>Writer</code> 69 * associated with the default <code>ScriptContext</code> of the associated <code>ScriptEngine</code> are used. 70 * 71 * @param bindings The bindings of attributes used for the <code>ENGINE_SCOPE</code>. 72 * 73 * @return The return value from the script execution 74 * 75 * @throws ScriptException if an error occurs. 76 */ 77 public Object eval(Bindings bindings) throws ScriptException { 78 79 ScriptContext ctxt = getEngine().getContext(); 80 81 if (bindings != null) { 82 SimpleScriptContext tempctxt = new SimpleScriptContext(); 83 tempctxt.setBindings(bindings, ScriptContext.ENGINE_SCOPE); 84 tempctxt.setBindings(ctxt.getBindings(ScriptContext.GLOBAL_SCOPE), 85 ScriptContext.GLOBAL_SCOPE); 86 tempctxt.setWriter(ctxt.getWriter()); 87 tempctxt.setReader(ctxt.getReader()); 88 tempctxt.setErrorWriter(ctxt.getErrorWriter()); 89 ctxt = tempctxt; 90 } 91 92 return eval(ctxt); 93 } 94 95 96 /** 97 * Executes the program stored in the <code>CompiledScript</code> object. The 98 * default <code>ScriptContext</code> of the associated <code>ScriptEngine</code> is used. 99 * The effect of calling this method is same as that of eval(getEngine().getContext()). 100 * 101 * @return The return value from the script execution 102 * 103 * @throws ScriptException if an error occurs. 104 */ 105 public Object eval() throws ScriptException { 106 return eval(getEngine().getContext()); 107 } 108 109 /** 110 * Returns the <code>ScriptEngine</code> whose <code>compile</code> method created this <code>CompiledScript</code>. 111 * The <code>CompiledScript</code> will execute in this engine. 112 * 113 * @return The <code>ScriptEngine</code> that created this <code>CompiledScript</code> 114 */ 115 public abstract ScriptEngine getEngine(); 116 117} 118