org.apache.hadoop.hive.ql.debug.Utils.java Source code

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Here is the source code for org.apache.hadoop.hive.ql.debug.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 org.apache.hadoop.hive.ql.debug;

import java.io.File;
import java.io.IOException;
import java.io.UnsupportedEncodingException;
import java.lang.management.ManagementFactory;
import java.lang.reflect.Method;

import javax.management.MBeanServer;

import org.apache.commons.lang.StringUtils;
import org.slf4j.Logger;
import org.slf4j.LoggerFactory;

/**
 * Debug utility methods for Hive.
 */
public class Utils {
    private static final Logger LOG = LoggerFactory.getLogger(Utils.class.getName());
    private static final String HOTSPOT_BEAN_NAME = "com.sun.management:type=HotSpotDiagnostic";
    private static volatile Object hotspotMBean;
    private static final Method DUMP_HEAP_METHOD;
    private static final Class HOTSPOT_MXBEAN_CLASS;

    static {
        Class clazz;
        Method method;
        try {
            clazz = Class.forName("com.sun.management.HotSpotDiagnosticMXBean");
            method = clazz.getMethod("dumpHeap", String.class, Boolean.class);
        } catch (ClassNotFoundException ce) {
            LOG.error("com.sun.management.HotSpotDiagnosticMXBean is not supported.", ce);
            throw new RuntimeException(ce);
        } catch (NoSuchMethodException ne) {
            LOG.error("Failed to inject operation dumpHeap.", ne);
            throw new RuntimeException(ne);
        } catch (Exception e) {
            LOG.error(e.getMessage());
            throw new RuntimeException(e);
        }
        HOTSPOT_MXBEAN_CLASS = clazz;
        DUMP_HEAP_METHOD = method;
    }

    /**
     * Dumps process heap to a file in temp directoty.
     * @param args Strings to use to build a file name (dump_arg0_arg1_....).
     */
    public static void dumpHeapToTmp(String... args) {
        String tmpDir = System.getProperty("java.io.tmpdir");
        if (StringUtils.isBlank(tmpDir)) {
            tmpDir = "/tmp/";
        }
        String fileName = tmpDir + File.pathSeparatorChar + "dump";
        for (String arg : args) {
            fileName += "_" + arg;
        }
        fileName += "_" + System.nanoTime() + ".hprof";
        dumpHeap(fileName, true);
    }

    /**
     * Dumps process heap.
     * @param fileName File name to use.
     * @param live Whether to only dump live objects.
     */
    public static void dumpHeap(String fileName, boolean live) {
        if (hotspotMBean == null) {
            try {
                MBeanServer server = ManagementFactory.getPlatformMBeanServer();
                hotspotMBean = ManagementFactory.newPlatformMXBeanProxy(server, HOTSPOT_BEAN_NAME,
                        HOTSPOT_MXBEAN_CLASS);
            } catch (IOException e) {
                LOG.error(e.getMessage());
                throw new RuntimeException(e);
            }
        }
        if (DUMP_HEAP_METHOD != null) {
            try {
                DUMP_HEAP_METHOD.invoke(hotspotMBean, new Object[] { fileName, Boolean.valueOf(live) });
            } catch (RuntimeException re) {
                LOG.error(re.getMessage());
                throw re;
            } catch (Exception exp) {
                LOG.error(exp.getMessage());
                throw new RuntimeException(exp);
            }
        } else {
            LOG.error("Cannot find method dumpHeap() in com.sun.management.HotSpotDiagnosticMXBean.");
        }
    }

    /**
     * Outputs some bytes as hex w/printable characters prints.
     * Helpful debug method; c/p from HBase Bytes.
     * @param b Bytes.
     * @param off Offset.
     * @param len Length.
     * @return The string representation.
     */
    public static String toStringBinary(final byte[] b, int off, int len) {
        StringBuilder result = new StringBuilder();
        try {
            String first = new String(b, off, len, "ISO-8859-1");
            for (int i = 0; i < first.length(); ++i) {
                int ch = first.charAt(i) & 0xFF;
                if ((ch >= '0' && ch <= '9') || (ch >= 'A' && ch <= 'Z') || (ch >= 'a' && ch <= 'z')
                        || " `~!@#$%^&*()-_=+[]{}\\|;:'\",.<>/?".indexOf(ch) >= 0) {
                    result.append(first.charAt(i));
                } else {
                    result.append(String.format("\\x%02X", ch));
                }
            }
        } catch (UnsupportedEncodingException e) {
            throw new RuntimeException("ISO-8859-1 not supported?", e);
        }
        return result.toString();
    }
}