/**
* 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.camel.support;
import java.io.InputStream;
import org.apache.camel.CamelContext;
import org.apache.camel.CamelContextAware;
import org.apache.camel.ExpressionIllegalSyntaxException;
import org.apache.camel.IsSingleton;
import org.apache.camel.spi.Language;
import org.apache.camel.util.IOHelper;
import org.apache.camel.util.ResourceHelper;
/**
* Base language for {@link Language} implementations.
*/
public abstract class LanguageSupport implements Language, IsSingleton, CamelContextAware {
public static final String RESOURCE = "resource:";
private CamelContext camelContext;
public CamelContext getCamelContext() {
return camelContext;
}
public void setCamelContext(CamelContext camelContext) {
this.camelContext = camelContext;
}
@Override
public boolean isSingleton() {
return true;
}
/**
* Loads the resource if the given expression is referring to an external resource by using
* the syntax <tt>resource:scheme:uri<tt>.
* If the expression is not referring to a resource, then its returned as is.
* <p/>
* For example <tt>resource:classpath:mygroovy.groovy</tt> to refer to a groovy script on the classpath.
*
* @param expression the expression
* @return the expression
* @throws ExpressionIllegalSyntaxException is thrown if error loading the resource
*/
protected String loadResource(String expression) throws ExpressionIllegalSyntaxException {
if (camelContext != null && expression.startsWith(RESOURCE)) {
String uri = expression.substring(RESOURCE.length());
InputStream is = null;
try {
is = ResourceHelper.resolveMandatoryResourceAsInputStream(camelContext, uri);
expression = camelContext.getTypeConverter().mandatoryConvertTo(String.class, is);
} catch (Exception e) {
throw new ExpressionIllegalSyntaxException(expression, e);
} finally {
IOHelper.close(is);
}
}
return expression;
}
}