001 /* 002 $Id: GroovyEngine.java 4166 2006-10-25 07:07:33Z paulk $ 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 protected GroovyShell shell; 069 070 /* 071 * Convert a non java class name to a java classname 072 * This is used to convert a script name to a name 073 * that can be used as a classname with the script is 074 * loaded in GroovyClassloader#load() 075 * The method simply replaces any invalid characters 076 * with "_". 077 */ 078 private String convertToValidJavaClassname(String inName) { 079 if (inName == null || inName.equals("")) { 080 return "_"; 081 } 082 StringBuffer output = new StringBuffer(inName.length()); 083 boolean firstChar = true; 084 for (int i = 0; i < inName.length(); ++i) { 085 char ch = inName.charAt(i); 086 if (firstChar && !Character.isJavaIdentifierStart(ch)) { 087 ch = '_'; 088 } else if (!firstChar 089 && !(Character.isJavaIdentifierPart(ch) || ch == '.')) { 090 ch = '_'; 091 } 092 firstChar = (ch == '.'); 093 output.append(ch); 094 } 095 return output.toString(); 096 } 097 098 /** 099 * Allow an anonymous function to be declared and invoked 100 */ 101 public Object apply(String source, int lineNo, int columnNo, Object funcBody, Vector paramNames, 102 Vector arguments) throws BSFException { 103 Object object = eval(source, lineNo, columnNo, funcBody); 104 if (object instanceof Closure) { 105 // lets call the function 106 Closure closure = (Closure) object; 107 return closure.call(arguments.toArray()); 108 } 109 return object; 110 } 111 112 /** 113 * Call the named method of the given object. 114 */ 115 public Object call(Object object, String method, Object[] args) throws BSFException { 116 return InvokerHelper.invokeMethod(object, method, args); 117 } 118 119 /** 120 * Evaluate an expression. 121 */ 122 public Object eval(String source, int lineNo, int columnNo, Object script) throws BSFException { 123 try { 124 source = convertToValidJavaClassname(source); 125 return getEvalShell().evaluate(script.toString(), source); 126 } catch (Exception e) { 127 throw new BSFException(BSFException.REASON_EXECUTION_ERROR, "exception from Groovy: " + e, e); 128 } 129 } 130 131 /** 132 * Execute a script. 133 */ 134 public void exec(String source, int lineNo, int columnNo, Object script) throws BSFException { 135 try { 136 // use evaluate to pass in the BSF variables 137 source = convertToValidJavaClassname(source); 138 getEvalShell().evaluate(script.toString(), source); 139 } catch (Exception e) { 140 throw new BSFException(BSFException.REASON_EXECUTION_ERROR, "exception from Groovy: " + e, e); 141 } 142 } 143 144 /** 145 * Initialize the engine. 146 */ 147 public void initialize(BSFManager mgr, String lang, Vector declaredBeans) throws BSFException { 148 super.initialize(mgr, lang, declaredBeans); 149 150 // create a shell 151 shell = new GroovyShell(mgr.getClassLoader()); 152 153 // register the mgr with object name "bsf" 154 shell.setVariable("bsf", new BSFFunctions(mgr, this)); 155 156 int size = declaredBeans.size(); 157 for (int i = 0; i < size; i++) { 158 declareBean((BSFDeclaredBean) declaredBeans.elementAt(i)); 159 } 160 } 161 162 /** 163 * Declare a bean 164 */ 165 public void declareBean(BSFDeclaredBean bean) throws BSFException { 166 shell.setVariable(bean.name, bean.bean); 167 } 168 169 /** 170 * Undeclare a previously declared bean. 171 */ 172 public void undeclareBean(BSFDeclaredBean bean) throws BSFException { 173 shell.setVariable(bean.name, null); 174 } 175 176 /** 177 * @return a newly created GroovyShell using the same variable scope but a new class loader 178 */ 179 protected GroovyShell getEvalShell() { 180 return new GroovyShell(shell); 181 } 182 }