001 /*
002 $Id: Script.java,v 1.18 2004/12/27 10:31:24 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 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: 1.18 $
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(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 }