/*
* Copyright 2013 Cloudera Inc.
*
* 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 com.cloudera.cdk.morphline.stdlib;
import java.util.Collection;
import java.util.Collections;
import javax.script.ScriptException;
import org.slf4j.Logger;
import com.cloudera.cdk.morphline.api.Command;
import com.cloudera.cdk.morphline.api.CommandBuilder;
import com.cloudera.cdk.morphline.api.MorphlineCompilationException;
import com.cloudera.cdk.morphline.api.MorphlineContext;
import com.cloudera.cdk.morphline.api.MorphlineRuntimeException;
import com.cloudera.cdk.morphline.api.Record;
import com.cloudera.cdk.morphline.base.AbstractCommand;
import com.cloudera.cdk.morphline.base.Configs;
import com.cloudera.cdk.morphline.base.Fields;
import com.cloudera.cdk.morphline.scriptengine.java.ScriptEvaluator;
import com.typesafe.config.Config;
/**
* The "java" command compiles the given Java code block, wrapped into a Java method with a boolean
* return type and several parameters, along with a Java class definition that contains the given
* import statements. The code block can then be executed many times.
*/
public final class JavaBuilder implements CommandBuilder {
@Override
public Collection<String> getNames() {
return Collections.singletonList("java");
}
@Override
public Command build(Config config, Command parent, Command child, MorphlineContext context) {
try {
return new Java(this, config, parent, child, context);
} catch (ScriptException e) {
throw new MorphlineCompilationException("Cannot compile script", config, e);
}
}
///////////////////////////////////////////////////////////////////////////////
// Nested classes:
///////////////////////////////////////////////////////////////////////////////
private static final class Java extends AbstractCommand {
private final ScriptEvaluator<Boolean> script;
private static final String DEFAULT_IMPORTS =
"import java.util.*;\n" +
"import java.io.*;\n" +
"import java.text.*;\n" +
"import com.google.common.base.*;\n" +
"import com.google.common.collect.*;\n" +
"import " + Record.class.getPackage().getName() + ".*;\n" +
"import " + Fields.class.getName() + ";\n" +
"import " + Configs.class.getName() + ";\n" +
"";
public Java(CommandBuilder builder, Config config, Command parent, Command child, MorphlineContext context) throws ScriptException {
super(builder, config, parent, child, context);
String javaImports = getConfigs().getString(config, "imports", DEFAULT_IMPORTS);
String javaCodeBlock = getConfigs().getString(config, "code");
this.script = new ScriptEvaluator<Boolean>(
javaImports,
javaCodeBlock,
Boolean.class,
new String[] {"record", "config", "parent", "child", "context", "logger"},
new Class[] {Record.class, Config.class, Command.class, Command.class, MorphlineContext.class, Logger.class},
javaCodeBlock
);
validateArguments();
}
@Override
protected boolean doProcess(Record record) {
try {
return script.evaluate(record, getConfig(), this, getChild(), getContext(), LOG);
} catch (ScriptException e) {
throw new MorphlineRuntimeException("Cannot execute script", e);
}
}
}
}