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/*
* Licensed to the Apache Software Foundation (ASF) under one or more
* contributor license agreements. See the NOTICE file distributed with
* this work for additional information regarding copyright ownership.
* The ASF licenses this file to You 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.jexl2.scripting;
import java.util.Arrays;
import java.util.Collections;
import java.util.List;
import javax.script.ScriptEngine;
import javax.script.ScriptEngineFactory;
import org.apache.commons.jexl2.JexlEngine;
import org.apache.commons.jexl2.parser.StringParser;
/**
* Implements the Jexl ScriptEngineFactory for JSF-223.
*
* Supports the following:
* Language short names: "JEXL", "Jexl", "jexl"
* Extension: "jexl"
*
*
* See
* Java Scripting API
* Javadoc.
* @since 2.0
*/
public class JexlScriptEngineFactory implements ScriptEngineFactory {
/** {@inheritDoc} */
public String getEngineName() {
return "JEXL Engine";
}
/** {@inheritDoc} */
public String getEngineVersion() {
return "1.0"; // ensure this is updated if function changes are made to this class
}
/** {@inheritDoc} */
public String getLanguageName() {
return "JEXL";
}
/** {@inheritDoc} */
public String getLanguageVersion() {
return "2.0"; // TODO this should be derived from the actual version
}
/** {@inheritDoc} */
public String getMethodCallSyntax(String obj, String m, String... args) {
StringBuilder sb = new StringBuilder();
sb.append(obj);
sb.append('.');
sb.append(m);
sb.append('(');
boolean needComma = false;
for(String arg : args){
if (needComma) {
sb.append(',');
}
sb.append(arg);
needComma = true;
}
sb.append(')');
return sb.toString();
}
/** {@inheritDoc} */
public List getExtensions() {
return Collections.unmodifiableList(Arrays.asList("jexl"));
}
/** {@inheritDoc} */
public List getMimeTypes() {
return Collections.unmodifiableList(Arrays.asList("application/x-jexl"));
}
/** {@inheritDoc} */
public List getNames() {
return Collections.unmodifiableList(Arrays.asList("JEXL", "Jexl", "jexl"));
}
/** {@inheritDoc} */
public String getOutputStatement(String toDisplay) {
if (toDisplay == null) {
return "JEXL.out.print(null)";
} else {
return "JEXL.out.print("+StringParser.escapeString(toDisplay)+")";
}
}
/** {@inheritDoc} */
public Object getParameter(String key) {
if (key.equals(ScriptEngine.ENGINE)) {
return getEngineName();
} else if (key.equals(ScriptEngine.ENGINE_VERSION)) {
return getEngineVersion();
} else if (key.equals(ScriptEngine.NAME)) {
return getNames();
} else if (key.equals(ScriptEngine.LANGUAGE)) {
return getLanguageName();
} else if(key.equals(ScriptEngine.LANGUAGE_VERSION)) {
return getLanguageVersion();
} else if (key.equals("THREADING")) {
/*
* To implement multithreading, the scripting engine context (inherited from AbstractScriptEngine)
* would need to be made thread-safe; so would the setContext/getContext methods.
* It is easier to share the underlying Uberspect and JEXL engine instance, especially
* with an expression cache.
*/
return null;
}
return null;
}
/** {@inheritDoc} */
public String getProgram(String... statements) {
StringBuilder sb = new StringBuilder();
for(String statement : statements){
sb.append(JexlEngine.cleanExpression(statement));
if (!statement.endsWith(";")){
sb.append(';');
}
}
return sb.toString();
}
/** {@inheritDoc} */
public ScriptEngine getScriptEngine() {
JexlScriptEngine engine = new JexlScriptEngine(this);
return engine;
}
}