本文整理汇总了Java中org.apache.hadoop.hdfs.DistributedFileSystem.append方法的典型用法代码示例。如果您正苦于以下问题:Java DistributedFileSystem.append方法的具体用法?Java DistributedFileSystem.append怎么用?Java DistributedFileSystem.append使用的例子?那么, 这里精选的方法代码示例或许可以为您提供帮助。您也可以进一步了解该方法所在类org.apache.hadoop.hdfs.DistributedFileSystem
的用法示例。
在下文中一共展示了DistributedFileSystem.append方法的2个代码示例,这些例子默认根据受欢迎程度排序。您可以为喜欢或者感觉有用的代码点赞,您的评价将有助于系统推荐出更棒的Java代码示例。
示例1: testAddBlockUC
import org.apache.hadoop.hdfs.DistributedFileSystem; //导入方法依赖的package包/类
/**
* Test adding new blocks but without closing the corresponding the file
*/
@Test
public void testAddBlockUC() throws Exception {
DistributedFileSystem fs = cluster.getFileSystem();
final Path file1 = new Path("/file1");
DFSTestUtil.createFile(fs, file1, BLOCKSIZE - 1, REPLICATION, 0L);
FSDataOutputStream out = null;
try {
// append files without closing the streams
out = fs.append(file1);
String appendContent = "appending-content";
out.writeBytes(appendContent);
((DFSOutputStream) out.getWrappedStream()).hsync(
EnumSet.of(SyncFlag.UPDATE_LENGTH));
// restart NN
cluster.restartNameNode(true);
FSDirectory fsdir = cluster.getNamesystem().getFSDirectory();
INodeFile fileNode = fsdir.getINode4Write(file1.toString()).asFile();
BlockInfoContiguous[] fileBlocks = fileNode.getBlocks();
assertEquals(2, fileBlocks.length);
assertEquals(BLOCKSIZE, fileBlocks[0].getNumBytes());
assertEquals(BlockUCState.COMPLETE, fileBlocks[0].getBlockUCState());
assertEquals(appendContent.length() - 1, fileBlocks[1].getNumBytes());
assertEquals(BlockUCState.UNDER_CONSTRUCTION,
fileBlocks[1].getBlockUCState());
} finally {
if (out != null) {
out.close();
}
}
}
示例2: testHSyncOperation
import org.apache.hadoop.hdfs.DistributedFileSystem; //导入方法依赖的package包/类
private void testHSyncOperation(boolean testWithAppend) throws IOException {
Configuration conf = new HdfsConfiguration();
MiniDFSCluster cluster = new MiniDFSCluster.Builder(conf).build();
final DistributedFileSystem fs = cluster.getFileSystem();
final Path p = new Path("/testHSync/foo");
final int len = 1 << 16;
FSDataOutputStream out = fs.create(p, FsPermission.getDefault(),
EnumSet.of(CreateFlag.CREATE, CreateFlag.OVERWRITE, CreateFlag.SYNC_BLOCK),
4096, (short) 1, len, null);
if (testWithAppend) {
// re-open the file with append call
out.close();
out = fs.append(p, EnumSet.of(CreateFlag.APPEND, CreateFlag.SYNC_BLOCK),
4096, null);
}
out.hflush();
// hflush does not sync
checkSyncMetric(cluster, 0);
out.hsync();
// hsync on empty file does nothing
checkSyncMetric(cluster, 0);
out.write(1);
checkSyncMetric(cluster, 0);
out.hsync();
checkSyncMetric(cluster, 1);
// avoiding repeated hsyncs is a potential future optimization
out.hsync();
checkSyncMetric(cluster, 2);
out.hflush();
// hflush still does not sync
checkSyncMetric(cluster, 2);
out.close();
// close is sync'ing
checkSyncMetric(cluster, 3);
// same with a file created with out SYNC_BLOCK
out = fs.create(p, FsPermission.getDefault(),
EnumSet.of(CreateFlag.CREATE, CreateFlag.OVERWRITE),
4096, (short) 1, len, null);
out.hsync();
checkSyncMetric(cluster, 3);
out.write(1);
checkSyncMetric(cluster, 3);
out.hsync();
checkSyncMetric(cluster, 4);
// repeated hsyncs
out.hsync();
checkSyncMetric(cluster, 5);
out.close();
// close does not sync (not opened with SYNC_BLOCK)
checkSyncMetric(cluster, 5);
cluster.shutdown();
}