scriptella.driver.janino.JaninoConnection Maven / Gradle / Ivy
/*
* Copyright 2006-2012 The Scriptella Project Team.
*
* 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 scriptella.driver.janino;
import scriptella.spi.AbstractConnection;
import scriptella.spi.ConnectionParameters;
import scriptella.spi.ParametersCallback;
import scriptella.spi.ProviderException;
import scriptella.spi.QueryCallback;
import scriptella.spi.Resource;
/**
* Scriptella connection adapter for Janino Script Evaluator.
* For configuration details and examples see overview page.
*
* @author Fyodor Kupolov
* @version 1.0
*/
public class JaninoConnection extends AbstractConnection {
private CodeCompiler compiler = new CodeCompiler();
/**
* Instantiates a new connection to Janino Script Evaluator.
* @param parameters connection parameters.
*/
public JaninoConnection(ConnectionParameters parameters) {
super(Driver.DIALECT_IDENTIFIER, parameters);
}
public void executeScript(Resource scriptContent, ParametersCallback parametersCallback) throws ProviderException {
JaninoScript s = compiler.compileScript(scriptContent);
s.setParametersCallback(parametersCallback);
try {
s.execute();
} catch (Exception e) {
throw guessErrorStatement(new JaninoProviderException(
"Script execution failed due to exception",e), scriptContent, s.getClass());
} finally {
//GC unused references
s.setParametersCallback(null);
}
}
/**
* Executes a query specified by its content.
*
*
* @param queryContent query content.
* @param parametersCallback callback to get parameter values.
* @param queryCallback callback to call for each result set element produced by this query.
* @see #executeScript(scriptella.spi.Resource, scriptella.spi.ParametersCallback)
*/
public void executeQuery(Resource queryContent, ParametersCallback parametersCallback, QueryCallback queryCallback) throws ProviderException {
JaninoQuery q = compiler.compileQuery(queryContent);
q.setParametersCallback(parametersCallback);
q.setQueryCallback(queryCallback);
try {
q.execute();
} catch (Exception e) {
throw guessErrorStatement(new JaninoProviderException(
"Query execution failed due to exception",e), queryContent, q.getClass());
} finally {
//GC unused references
q.setParametersCallback(null);
q.setQueryCallback(null);
}
}
/**
* Finds an error statement by introspecting the stack trace of exception.
* Error statement is fetched from content resource.
* @param content script content.
* @param e exception to introspect.
* @param scriptClass class to use when finding an error statement.
* @return the same exception with a guessed error statement.
*/
private static JaninoProviderException guessErrorStatement(JaninoProviderException e, Resource content, Class scriptClass) {
Throwable ex = e.getCause();
StackTraceElement[] trace = ex.getStackTrace();
final String scriptClassName = scriptClass.getName();
for (StackTraceElement el : trace) { //find the top most instance of generated class
String className = el.getClassName();
if (scriptClassName.equals(className)) {
String st = CodeCompiler.getLine(content, el.getLineNumber());
e.setErrorStatement(st);
break;
}
}
return e;
}
/**
* Closes the connection and releases all related resources.
*/
public void close() throws ProviderException {
compiler=null;
}
}