Examples with Random java.util.Random used on opensource projects

Example 96 with Random

use of java.util.Random in project hadoop by apache.

the class TestPread method datanodeRestartTest.

// test pread can survive datanode restarts
private void datanodeRestartTest(MiniDFSCluster cluster, FileSystem fileSys, Path name) throws IOException {
    // don't survive datanode restarts.
    if (simulatedStorage) {
        return;
    }
    int numBlocks = 1;
    assertTrue(numBlocks <= HdfsClientConfigKeys.DFS_CLIENT_MAX_BLOCK_ACQUIRE_FAILURES_DEFAULT);
    byte[] expected = new byte[numBlocks * blockSize];
    Random rand = new Random(seed);
    rand.nextBytes(expected);
    byte[] actual = new byte[numBlocks * blockSize];
    FSDataInputStream stm = fileSys.open(name);
    // read a block and get block locations cached as a result
    stm.readFully(0, actual);
    checkAndEraseData(actual, 0, expected, "Pread Datanode Restart Setup");
    // restart all datanodes. it is expected that they will
    // restart on different ports, hence, cached block locations
    // will no longer work.
    assertTrue(cluster.restartDataNodes());
    cluster.waitActive();
    // verify the block can be read again using the same InputStream 
    // (via re-fetching of block locations from namenode). there is a 
    // 3 sec sleep in chooseDataNode(), which can be shortened for 
    // this test if configurable.
    stm.readFully(0, actual);
    checkAndEraseData(actual, 0, expected, "Pread Datanode Restart Test");
}

Example 97 with Random

use of java.util.Random in project hadoop by apache.

the class TestCachedBlocksList method testMultipleLists.

@Test(timeout = 60000)
public void testMultipleLists() {
    DatanodeDescriptor[] datanodes = new DatanodeDescriptor[] { new DatanodeDescriptor(new DatanodeID("127.0.0.1", "localhost", "abcd", 5000, 5001, 5002, 5003)), new DatanodeDescriptor(new DatanodeID("127.0.1.1", "localhost", "efgh", 6000, 6001, 6002, 6003)) };
    CachedBlocksList[] lists = new CachedBlocksList[] { datanodes[0].getPendingCached(), datanodes[0].getCached(), datanodes[1].getPendingCached(), datanodes[1].getCached(), datanodes[1].getPendingUncached() };
    final int NUM_BLOCKS = 8000;
    CachedBlock[] blocks = new CachedBlock[NUM_BLOCKS];
    for (int i = 0; i < NUM_BLOCKS; i++) {
        blocks[i] = new CachedBlock(i, (short) i, true);
    }
    Random r = new Random(654);
    for (CachedBlocksList list : lists) {
        testAddElementsToList(list, blocks);
    }
    for (CachedBlocksList list : lists) {
        testRemoveElementsFromList(r, list, blocks);
    }
}

Example 98 with Random

use of java.util.Random in project hadoop by apache.

the class TestBlockTokenWithDFS method generateBytes.

public static byte[] generateBytes(int fileSize) {
    Random r = new Random();
    byte[] rawData = new byte[fileSize];
    r.nextBytes(rawData);
    return rawData;
}

Example 99 with Random

use of java.util.Random in project hadoop by apache.

the class TestEditLog method testFuzzSequences.

/**
   * "Fuzz" test for the edit log.
   *
   * This tests that we can read random garbage from the edit log without
   * crashing the JVM or throwing an unchecked exception.
   */
@Test
public void testFuzzSequences() throws IOException {
    final int MAX_GARBAGE_LENGTH = 512;
    final int MAX_INVALID_SEQ = 5000;
    // The seed to use for our random number generator.  When given the same
    // seed, Java.util.Random will always produce the same sequence of values.
    // This is important because it means that the test is deterministic and
    // repeatable on any machine.
    final int RANDOM_SEED = 123;
    Random r = new Random(RANDOM_SEED);
    for (int i = 0; i < MAX_INVALID_SEQ; i++) {
        byte[] garbage = new byte[r.nextInt(MAX_GARBAGE_LENGTH)];
        r.nextBytes(garbage);
        validateNoCrash(garbage);
    }
}

Example 100 with Random

use of java.util.Random in project hadoop by apache.

the class TestCodec method testSplitableCodec.

private void testSplitableCodec(Class<? extends SplittableCompressionCodec> codecClass) throws IOException {
    final long DEFLBYTES = 2 * 1024 * 1024;
    final Configuration conf = new Configuration();
    final Random rand = new Random();
    final long seed = rand.nextLong();
    LOG.info("seed: " + seed);
    rand.setSeed(seed);
    SplittableCompressionCodec codec = ReflectionUtils.newInstance(codecClass, conf);
    final FileSystem fs = FileSystem.getLocal(conf);
    final FileStatus infile = fs.getFileStatus(writeSplitTestFile(fs, rand, codec, DEFLBYTES));
    if (infile.getLen() > Integer.MAX_VALUE) {
        fail("Unexpected compression: " + DEFLBYTES + " -> " + infile.getLen());
    }
    final int flen = (int) infile.getLen();
    final Text line = new Text();
    final Decompressor dcmp = CodecPool.getDecompressor(codec);
    try {
        for (int pos = 0; pos < infile.getLen(); pos += rand.nextInt(flen / 8)) {
            // read from random positions, verifying that there exist two sequential
            // lines as written in writeSplitTestFile
            final SplitCompressionInputStream in = codec.createInputStream(fs.open(infile.getPath()), dcmp, pos, flen, SplittableCompressionCodec.READ_MODE.BYBLOCK);
            if (in.getAdjustedStart() >= flen) {
                break;
            }
            LOG.info("SAMPLE " + in.getAdjustedStart() + "," + in.getAdjustedEnd());
            final LineReader lreader = new LineReader(in);
            // ignore; likely partial
            lreader.readLine(line);
            if (in.getPos() >= flen) {
                break;
            }
            lreader.readLine(line);
            final int seq1 = readLeadingInt(line);
            lreader.readLine(line);
            if (in.getPos() >= flen) {
                break;
            }
            final int seq2 = readLeadingInt(line);
            assertEquals("Mismatched lines", seq1 + 1, seq2);
        }
    } finally {
        CodecPool.returnDecompressor(dcmp);
    }
    // remove on success
    fs.delete(infile.getPath().getParent(), true);
}