001 /* 002 $Id: Script.java,v 1.21 2005/10/03 18:07:35 tug 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 groovy.lang; 047 048 import org.codehaus.groovy.ast.expr.ArgumentListExpression; 049 import org.codehaus.groovy.control.CompilationFailedException; 050 import org.codehaus.groovy.runtime.InvokerHelper; 051 052 import java.io.File; 053 import java.io.IOException; 054 055 /** 056 * This object represents a Groovy script 057 * 058 * @author <a href="mailto:james@coredevelopers.net">James Strachan</a> 059 * @author Guillaume Laforge 060 * @version $Revision: 1.21 $ 061 */ 062 public abstract class Script extends GroovyObjectSupport { 063 private Binding binding = new Binding(); 064 065 protected Script() { 066 } 067 068 protected Script(Binding binding) { 069 this.binding = binding; 070 } 071 072 public Binding getBinding() { 073 return binding; 074 } 075 076 public void setBinding(Binding binding) { 077 this.binding = binding; 078 } 079 080 public Object getProperty(String property) { 081 //System.out.println("Script.getProperty for: " + property + " with binding: " + binding.getVariables()); 082 try { 083 return binding.getVariable(property); 084 } catch (MissingPropertyException e) { 085 return super.getProperty(property); 086 } 087 } 088 089 public void setProperty(String property, Object newValue) { 090 //System.out.println("Script.setProperty for: " + property + " with newValue: " + newValue); 091 binding.setVariable(property, newValue); 092 //System.out.println("binding are now: " + binding.getVariables()); 093 } 094 095 /** 096 * Invoke a method (or closure in the binding) defined. 097 * 098 * @param name method to call 099 * @param args arguments to pass to the method 100 * @return value 101 */ 102 public Object invokeMethod(String name, Object args) { 103 try { 104 return super.invokeMethod(name, args); 105 } 106 // if the method was not found in the current scope (the script's methods) 107 // let's try to see if there's a method closure with the same name in the binding 108 catch (MissingMethodException mme) { 109 try { 110 if (name.equals(mme.getMethod())) { 111 Object boundClosure = binding.getVariable(name); 112 if (boundClosure != null && boundClosure instanceof Closure) { 113 return ((Closure) boundClosure).call((Object[])args); 114 } else { 115 throw mme; 116 } 117 } else { 118 throw mme; 119 } 120 } catch (MissingPropertyException mpe) { 121 throw mme; 122 } 123 } 124 } 125 126 /** 127 * The main instance method of a script which has variables in scope 128 * as defined by the current {@link Binding} instance. 129 * 130 * @return 131 */ 132 public abstract Object run(); 133 134 // println helper methods 135 136 /** 137 * Prints a newline to the current 'out' variable which should be a PrintWriter 138 * or at least have a println() method defined on it. 139 * If there is no 'out' property then print to standard out. 140 */ 141 public void println() { 142 Object object; 143 144 try { 145 object = getProperty("out"); 146 } catch (MissingPropertyException e) { 147 System.out.println(); 148 return; 149 } 150 151 InvokerHelper.invokeMethod(object, "println", ArgumentListExpression.EMPTY_ARRAY); 152 } 153 154 /** 155 * Prints the value to the current 'out' variable which should be a PrintWriter 156 * or at least have a print() method defined on it. 157 * If there is no 'out' property then print to standard out. 158 */ 159 public void print(Object value) { 160 Object object; 161 162 try { 163 object = getProperty("out"); 164 } catch (MissingPropertyException e) { 165 System.out.print(value); 166 return; 167 } 168 169 InvokerHelper.invokeMethod(object, "print", new Object[]{value}); 170 } 171 172 /** 173 * Prints the value and a newline to the current 'out' variable which should be a PrintWriter 174 * or at least have a println() method defined on it. 175 * If there is no 'out' property then print to standard out. 176 */ 177 public void println(Object value) { 178 Object object; 179 180 try { 181 object = getProperty("out"); 182 } catch (MissingPropertyException e) { 183 System.out.println(value); 184 return; 185 } 186 187 InvokerHelper.invokeMethod(object, "println", new Object[]{value}); 188 } 189 190 /** 191 * A helper method to allow the dynamic evaluation of groovy expressions using this 192 * scripts binding as the variable scope 193 * 194 * @param expression is the Groovy script expression to evaluate 195 */ 196 public Object evaluate(String expression) throws CompilationFailedException, IOException { 197 GroovyShell shell = new GroovyShell(binding); 198 return shell.evaluate(expression); 199 } 200 201 /** 202 * A helper method to allow the dynamic evaluation of groovy expressions using this 203 * scripts binding as the variable scope 204 * 205 * @param file is the Groovy script to evaluate 206 */ 207 public Object evaluate(File file) throws CompilationFailedException, IOException { 208 GroovyShell shell = new GroovyShell(binding); 209 return shell.evaluate(file); 210 } 211 212 /** 213 * A helper method to allow scripts to be run taking command line arguments 214 */ 215 public void run(File file, String[] arguments) throws CompilationFailedException, IOException { 216 GroovyShell shell = new GroovyShell(binding); 217 shell.run(file, arguments); 218 } 219 }