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Posted to dev@commons.apache.org by di...@apache.org on 2006/04/03 13:22:31 UTC
svn commit: r391004 - in
/jakarta/commons/proper/jexl/trunk/src/java/org/apache/commons/jexl:
Script.java ScriptFactory.java ScriptImpl.java
Author: dion
Date: Mon Apr 3 04:22:29 2006
New Revision: 391004
URL: http://svn.apache.org/viewcvs?rev=391004&view=rev
Log:
Start of script implementation
Added:
jakarta/commons/proper/jexl/trunk/src/java/org/apache/commons/jexl/Script.java (with props)
jakarta/commons/proper/jexl/trunk/src/java/org/apache/commons/jexl/ScriptFactory.java (with props)
jakarta/commons/proper/jexl/trunk/src/java/org/apache/commons/jexl/ScriptImpl.java (with props)
Added: jakarta/commons/proper/jexl/trunk/src/java/org/apache/commons/jexl/Script.java
URL: http://svn.apache.org/viewcvs/jakarta/commons/proper/jexl/trunk/src/java/org/apache/commons/jexl/Script.java?rev=391004&view=auto
==============================================================================
--- jakarta/commons/proper/jexl/trunk/src/java/org/apache/commons/jexl/Script.java (added)
+++ jakarta/commons/proper/jexl/trunk/src/java/org/apache/commons/jexl/Script.java Mon Apr 3 04:22:29 2006
@@ -0,0 +1,34 @@
+/*
+ * Copyright 2002-2006 The Apache Software Foundation.
+ *
+ * Licensed under the Apache License, Version 2.0 (the "License");
+ * you may not use this file except in compliance with the License.
+ * You may obtain a copy of the License at
+ *
+ * http://www.apache.org/licenses/LICENSE-2.0
+ *
+ * Unless required by applicable law or agreed to in writing, software
+ * distributed under the License is distributed on an "AS IS" BASIS,
+ * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+ * See the License for the specific language governing permissions and
+ * limitations under the License.
+ */
+package org.apache.commons.jexl;
+
+public interface Script {
+ /**
+ * Executes the script with the variables contained in the
+ * supplied {@link JexlContext}.
+ *
+ * @param context A JexlContext containing variables.
+ * @return The result of this script, usually the result of the last statement.
+ */
+ Object execute(JexlContext context) throws Exception;
+
+ /**
+ * Returns the text of this Script.
+ * @return The script to be executed.
+ */
+ String getText();
+
+}
Propchange: jakarta/commons/proper/jexl/trunk/src/java/org/apache/commons/jexl/Script.java
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svn:keywords = Id
Added: jakarta/commons/proper/jexl/trunk/src/java/org/apache/commons/jexl/ScriptFactory.java
URL: http://svn.apache.org/viewcvs/jakarta/commons/proper/jexl/trunk/src/java/org/apache/commons/jexl/ScriptFactory.java?rev=391004&view=auto
==============================================================================
--- jakarta/commons/proper/jexl/trunk/src/java/org/apache/commons/jexl/ScriptFactory.java (added)
+++ jakarta/commons/proper/jexl/trunk/src/java/org/apache/commons/jexl/ScriptFactory.java Mon Apr 3 04:22:29 2006
@@ -0,0 +1,126 @@
+/*
+ * Copyright 2002-2006 The Apache Software Foundation.
+ *
+ * Licensed under the Apache License, Version 2.0 (the "License");
+ * you may not use this file except in compliance with the License.
+ * You may obtain a copy of the License at
+ *
+ * http://www.apache.org/licenses/LICENSE-2.0
+ *
+ * Unless required by applicable law or agreed to in writing, software
+ * distributed under the License is distributed on an "AS IS" BASIS,
+ * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+ * See the License for the specific language governing permissions and
+ * limitations under the License.
+ */
+package org.apache.commons.jexl;
+
+import java.io.StringReader;
+
+import org.apache.commons.jexl.parser.ASTJexlScript;
+import org.apache.commons.jexl.parser.Parser;
+import org.apache.commons.logging.Log;
+import org.apache.commons.logging.LogFactory;
+
+/**
+ * <p>
+ * Creates {@link Script}s. To create a JEXL Script, pass
+ * valid JEXL syntax to the static createScript() method:
+ * </p>
+ *
+ * <pre>
+ * String jexl = "y = x * 12 + 44; y = y * 4;";
+ * Script script = ScriptFactory.createScript( jexl );
+ * </pre>
+ *
+ * <p>
+ * When an {@link Script} is created, the JEXL syntax is
+ * parsed and verified.
+ * </p>
+ * @since 1.1
+ * @version $Id$
+ */
+public class ScriptFactory {
+
+ /** The Log to which all ScriptFactory messages will be logged.*/
+ protected static Log log =
+ LogFactory.getLog("org.apache.commons.jexl.ScriptFactory");
+
+ /**
+ * The singleton ScriptFactory also holds a single instance of {@link Parser}.
+ * When parsing expressions, ScriptFactory synchronizes on Parser.
+ */
+ protected static Parser parser = new Parser(new StringReader(";")); //$NON-NLS-1$
+
+ /**
+ * ScriptFactory is a singleton and this is the private
+ * instance fufilling that pattern.
+ */
+ protected static ScriptFactory factory = new ScriptFactory();
+
+ /**
+ * Private constructor, the single instance is always obtained
+ * with a call to getInstance().
+ */
+ private ScriptFactory(){}
+
+ /**
+ * Returns the single instance of ScriptFactory.
+ * @return the instance of ScriptFactory.
+ */
+ protected static ScriptFactory getInstance()
+ {
+ return factory;
+ }
+
+ /**
+ * Creates a Script from a String containing valid JEXL syntax.
+ * This method parses the script which validates the syntax.
+ *
+ * @param scriptText A String containing valid JEXL syntax
+ * @return A {@link Script} which can be executed with a {@link JexlContext}.
+ * @throws Exception An exception can be thrown if there is a problem parsing the script.
+ */
+ public static Script createScript(String scriptText) throws Exception
+ {
+ return getInstance().newScript(scriptText);
+ }
+
+
+ /**
+ * Creates a new Script based on the string.
+ *
+ * @param scriptText valid Jexl script
+ * @return Script a new script
+ * @throws Exception for a variety of reasons - mostly malformed scripts
+ */
+ protected Script newScript(String scriptText) throws Exception {
+ String cleanText = cleanScript(scriptText);
+ // Parse the Expression
+ ASTJexlScript tree;
+ synchronized(parser)
+ {
+ log.debug( "Parsing script: " + cleanText);
+ tree = (ASTJexlScript) parser.parse(new StringReader(cleanText));
+ }
+
+ return new ScriptImpl(cleanText, tree);
+
+ }
+
+ /**
+ * @todo move to ParseUtils?
+ * Trims the expression and adds a semi-colon if missing.
+ * @param expression to clean
+ * @return trimmed expression ending in a semi-colon
+ */
+ private String cleanScript(String script) {
+ String expr = script.trim();
+ if (!expr.endsWith(";"))
+ {
+ expr += ";";
+ }
+ return expr;
+ }
+
+}
Propchange: jakarta/commons/proper/jexl/trunk/src/java/org/apache/commons/jexl/ScriptFactory.java
------------------------------------------------------------------------------
svn:keywords = Id
Added: jakarta/commons/proper/jexl/trunk/src/java/org/apache/commons/jexl/ScriptImpl.java
URL: http://svn.apache.org/viewcvs/jakarta/commons/proper/jexl/trunk/src/java/org/apache/commons/jexl/ScriptImpl.java?rev=391004&view=auto
==============================================================================
--- jakarta/commons/proper/jexl/trunk/src/java/org/apache/commons/jexl/ScriptImpl.java (added)
+++ jakarta/commons/proper/jexl/trunk/src/java/org/apache/commons/jexl/ScriptImpl.java Mon Apr 3 04:22:29 2006
@@ -0,0 +1,48 @@
+/*
+ * Copyright 2002,2004 The Apache Software Foundation.
+ *
+ * Licensed under the Apache License, Version 2.0 (the "License");
+ * you may not use this file except in compliance with the License.
+ * You may obtain a copy of the License at
+ *
+ * http://www.apache.org/licenses/LICENSE-2.0
+ *
+ * Unless required by applicable law or agreed to in writing, software
+ * distributed under the License is distributed on an "AS IS" BASIS,
+ * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+ * See the License for the specific language governing permissions and
+ * limitations under the License.
+ */
+
+package org.apache.commons.jexl;
+
+import org.apache.commons.jexl.parser.ASTJexlScript;
+
+public class ScriptImpl implements Script {
+
+ /** text of the script */
+ private String text;
+ /** syntax tree */
+ private ASTJexlScript parsedScript;
+
+ public ScriptImpl(String scriptText, ASTJexlScript scriptTree) {
+ text = scriptText;
+ parsedScript = scriptTree;
+ }
+
+ /**
+ * @see Script#execute(JexlContext)
+ */
+ public Object execute(JexlContext context) throws Exception {
+ // TODO Auto-generated method stub
+ return parsedScript.value(context);
+ }
+
+ /**
+ * @see Script#getText()
+ */
+ public String getText() {
+ return text;
+ }
+
+}
Propchange: jakarta/commons/proper/jexl/trunk/src/java/org/apache/commons/jexl/ScriptImpl.java
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svn:keywords = Id
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