com.cloudera.livy.rsc.Utils.java Source code

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Here is the source code for com.cloudera.livy.rsc.Utils.java

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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 com.cloudera.livy.rsc;

import java.util.concurrent.ThreadFactory;
import java.util.concurrent.atomic.AtomicInteger;

import io.netty.util.concurrent.Future;
import io.netty.util.concurrent.GenericFutureListener;

/**
 * A few simple utility functions used by the code, mostly to avoid a direct dependency
 * on Guava.
 */
public class Utils {

    public static void checkArgument(boolean condition) {
        if (!condition) {
            throw new IllegalArgumentException();
        }
    }

    public static void checkArgument(boolean condition, String msg, Object... args) {
        if (!condition) {
            throw new IllegalArgumentException(String.format(msg, args));
        }
    }

    public static void checkState(boolean condition, String msg, Object... args) {
        if (!condition) {
            throw new IllegalStateException(String.format(msg, args));
        }
    }

    public static void checkNotNull(Object o) {
        if (o == null) {
            throw new NullPointerException();
        }
    }

    public static RuntimeException propagate(Throwable t) {
        if (t instanceof RuntimeException) {
            throw (RuntimeException) t;
        } else {
            throw new RuntimeException(t);
        }
    }

    public static ThreadFactory newDaemonThreadFactory(final String nameFormat) {
        return new ThreadFactory() {

            private final AtomicInteger threadId = new AtomicInteger();

            @Override
            public Thread newThread(Runnable r) {
                Thread t = new Thread(r);
                t.setName(String.format(nameFormat, threadId.incrementAndGet()));
                t.setDaemon(true);
                return t;
            }

        };
    }

    public static String join(Iterable<String> strs, String sep) {
        StringBuilder sb = new StringBuilder();
        for (String s : strs) {
            if (s != null) {
                sb.append(s).append(sep);
            }
        }
        if (sb.length() > 0) {
            sb.setLength(sb.length() - sep.length());
        }
        return sb.toString();
    }

    public static String stackTraceAsString(Throwable t) {
        StringBuilder sb = new StringBuilder();
        sb.append(t.getClass().getName()).append(": ").append(t.getMessage());
        for (StackTraceElement e : t.getStackTrace()) {
            sb.append("\n");
            sb.append(e.toString());
        }
        return sb.toString();
    }

    public static <T> void addListener(Future<T> future, final FutureListener<T> lsnr) {
        future.addListener(new GenericFutureListener<Future<T>>() {
            @Override
            public void operationComplete(Future<T> f) throws Exception {
                if (f.isSuccess()) {
                    lsnr.onSuccess(f.get());
                } else {
                    lsnr.onFailure(f.cause());
                }
            }
        });
    }

    private Utils() {
    }

}