001 /* 002 $Id: GroovyEngine.java,v 1.10 2004/12/27 10:31:26 spullara Exp $ 003 004 Copyright 2003 (C) James Strachan and Bob Mcwhirter. All Rights Reserved. 005 006 Redistribution and use of this software and associated documentation 007 ("Software"), with or without modification, are permitted provided 008 that the following conditions are met: 009 010 1. Redistributions of source code must retain copyright 011 statements and notices. Redistributions must also contain a 012 copy of this document. 013 014 2. Redistributions in binary form must reproduce the 015 above copyright notice, this list of conditions and the 016 following disclaimer in the documentation and/or other 017 materials provided with the distribution. 018 019 3. The name "groovy" must not be used to endorse or promote 020 products derived from this Software without prior written 021 permission of The Codehaus. For written permission, 022 please contact info@codehaus.org. 023 024 4. Products derived from this Software may not be called "groovy" 025 nor may "groovy" appear in their names without prior written 026 permission of The Codehaus. "groovy" is a registered 027 trademark of The Codehaus. 028 029 5. Due credit should be given to The Codehaus - 030 http://groovy.codehaus.org/ 031 032 THIS SOFTWARE IS PROVIDED BY THE CODEHAUS AND CONTRIBUTORS 033 ``AS IS'' AND ANY EXPRESSED OR IMPLIED WARRANTIES, INCLUDING, BUT 034 NOT LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND 035 FITNESS FOR A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL 036 THE CODEHAUS OR ITS CONTRIBUTORS BE LIABLE FOR ANY DIRECT, 037 INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES 038 (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR 039 SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) 040 HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, 041 STRICT LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) 042 ARISING IN ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED 043 OF THE POSSIBILITY OF SUCH DAMAGE. 044 045 */ 046 package org.codehaus.groovy.bsf; 047 048 import groovy.lang.Closure; 049 import groovy.lang.GroovyShell; 050 import org.apache.bsf.BSFDeclaredBean; 051 import org.apache.bsf.BSFException; 052 import org.apache.bsf.BSFManager; 053 import org.apache.bsf.util.BSFEngineImpl; 054 import org.apache.bsf.util.BSFFunctions; 055 import org.codehaus.groovy.runtime.InvokerHelper; 056 057 import java.util.Vector; 058 059 /** 060 * A BSF Engine for the <a href="http://groovy.codehaus.org/">Groovy</a> 061 * scripting language. 062 * <p/> 063 * It's derived from the Jython / JPython engine 064 * 065 * @author James Strachan 066 */ 067 public class GroovyEngine extends BSFEngineImpl { 068 private static final String[] EMPTY_ARGS = { 069 }; 070 071 protected GroovyShell shell; 072 073 /** 074 * Convert a non java class name to a java classname 075 * This is used to convert a script name to a name 076 * that can be used as a classname with the script is 077 * loaded in GroovyClassloader#load() 078 * The method simply replaces any invalid characters 079 * with "_". 080 */ 081 private String convertToValidJavaClassname(String inName) { 082 if (inName == null || inName.equals("")) { 083 return "_"; 084 } 085 StringBuffer output = new StringBuffer(inName.length()); 086 boolean firstChar = true; 087 for (int i = 0; i < inName.length(); ++i) { 088 char ch = inName.charAt(i); 089 if (firstChar && !Character.isJavaIdentifierStart(ch)) { 090 ch = '_'; 091 } else if (!firstChar 092 && !(Character.isJavaIdentifierPart(ch) || ch == '.')) { 093 ch = '_'; 094 } 095 firstChar = (ch == '.'); 096 output.append(ch); 097 } 098 return output.toString(); 099 } 100 101 /** 102 * Allow an anonymous function to be declared and invoked 103 */ 104 public Object apply(java.lang.String source, 105 int lineNo, 106 int columnNo, 107 Object funcBody, 108 Vector paramNames, 109 Vector arguments) 110 throws BSFException { 111 112 Object object = eval(source, lineNo, columnNo, funcBody); 113 if (object instanceof Closure) { 114 // lets call the function 115 116 /** @todo we could turn the 2 vectors into a Map */ 117 Closure closure = (Closure) object; 118 return closure.call(arguments.toArray()); 119 } 120 return object; 121 } 122 123 /** 124 * Call the named method of the given object. 125 */ 126 public Object call(Object object, String method, Object[] args) throws BSFException { 127 return InvokerHelper.invokeMethod(object, method, args); 128 } 129 130 /** 131 * Declare a bean 132 */ 133 public void declareBean(BSFDeclaredBean bean) throws BSFException { 134 //System.out.println("Declaring bean: " + bean.name + " value: " + bean.bean); 135 shell.setVariable(bean.name, bean.bean); 136 } 137 138 /** 139 * Evaluate an expression. 140 */ 141 public Object eval(String source, int lineNo, int columnNo, Object script) throws BSFException { 142 try { 143 source = convertToValidJavaClassname(source); 144 Object result = getEvalShell().evaluate(script.toString(), source); 145 return result; 146 } catch (Exception e) { 147 throw new BSFException(BSFException.REASON_EXECUTION_ERROR, "exception from Groovy: " + e, e); 148 } 149 } 150 151 /** 152 * Execute a script. 153 */ 154 public void exec(String source, int lineNo, int columnNo, Object script) throws BSFException { 155 try { 156 // use evaluate to pass in the BSF variables 157 source = convertToValidJavaClassname(source); 158 getEvalShell().evaluate(script.toString(), source); 159 //getEvalShell().run(script.toString(), source, EMPTY_ARGS); 160 } catch (Exception e) { 161 throw new BSFException(BSFException.REASON_EXECUTION_ERROR, "exception from Groovy: " + e, e); 162 } 163 } 164 165 /** 166 * Initialize the engine. 167 */ 168 public void initialize(BSFManager mgr, String lang, Vector declaredBeans) throws BSFException { 169 super.initialize(mgr, lang, declaredBeans); 170 171 // create a shell 172 shell = new GroovyShell(mgr.getClassLoader()); 173 174 // register the mgr with object name "bsf" 175 shell.setVariable("bsf", new BSFFunctions(mgr, this)); 176 177 int size = declaredBeans.size(); 178 for (int i = 0; i < size; i++) { 179 declareBean((BSFDeclaredBean) declaredBeans.elementAt(i)); 180 } 181 } 182 183 /** 184 * Undeclare a previously declared bean. 185 */ 186 public void undeclareBean(BSFDeclaredBean bean) throws BSFException { 187 shell.setVariable(bean.name, null); 188 } 189 190 /** 191 * @return a newly created GroovyShell using the same variable scope but a new class loader 192 */ 193 protected GroovyShell getEvalShell() { 194 return new GroovyShell(shell); 195 } 196 }