J. Duke | 319a3b9 | 2007-12-01 00:00:00 +0000 | [diff] [blame^] | 1 | /* |
| 2 | * Copyright 2005 Sun Microsystems, Inc. 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. Sun designates this |
| 8 | * particular file as subject to the "Classpath" exception as provided |
| 9 | * by Sun 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 Sun Microsystems, Inc., 4150 Network Circle, Santa Clara, |
| 22 | * CA 95054 USA or visit www.sun.com if you need additional information or |
| 23 | * have any questions. |
| 24 | */ |
| 25 | |
| 26 | package javax.script; |
| 27 | |
| 28 | import 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 tne <code>CompiledScript</code> may visible during subsequent executions of scripts by the engine. |
| 40 | * |
| 41 | * @author Mike Grogan |
| 42 | * @since 1.6 |
| 43 | */ |
| 44 | public 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> wbose <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 | } |