org.apache.flink.runtime.util.ClusterEntrypointUtils Maven / Gradle / Ivy
/*
* 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.flink.runtime.util;
import org.apache.flink.configuration.ConfigConstants;
import javax.annotation.Nullable;
import java.io.File;
import java.util.Optional;
/**
* Utility class for {@link org.apache.flink.runtime.entrypoint.ClusterEntrypoint}.
*/
public final class ClusterEntrypointUtils {
private ClusterEntrypointUtils() {
throw new UnsupportedOperationException("This class should not be instantiated.");
}
/**
* Tries to find the user library directory.
*
* @return the user library directory if it exits, returns {@link Optional#empty()} if there is none
*/
public static Optional tryFindUserLibDirectory() {
final File flinkHomeDirectory = deriveFlinkHomeDirectoryFromLibDirectory();
final File usrLibDirectory = new File(flinkHomeDirectory, ConfigConstants.DEFAULT_FLINK_USR_LIB_DIR);
if (!usrLibDirectory.isDirectory()) {
return Optional.empty();
}
return Optional.of(usrLibDirectory);
}
@Nullable
private static File deriveFlinkHomeDirectoryFromLibDirectory() {
final String libDirectory = System.getenv().get(ConfigConstants.ENV_FLINK_LIB_DIR);
if (libDirectory == null) {
return null;
} else {
return new File(libDirectory).getParentFile();
}
}
}