@Override
public void append(HLog.Entry entry) throws IOException {
entry.setCompressionContext(compressionContext);
try {
this.writer.append(entry.getKey(), entry.getEdit());
} catch (NullPointerException npe) {
// Concurrent close...
throw new IOException(npe);
}
}
@Override
public HLog.Entry next(HLog.Entry reuse) throws IOException {
this.entryStart = this.reader.getPosition();
boolean b = true;
if (nextQueue.isEmpty()) { // Read the whole thing at once and fake reading
while (b == true) {
HLogKey key = HLog.newKey(conf);
WALEdit val = new WALEdit();
HLog.Entry e = new HLog.Entry(key, val);
codec.setCompression(compressionContext);
e.getEdit().setCodec(codec);
if (compressionContext != null) {
e.getKey().setCompressionContext(compressionContext);
}
b = this.reader.next(e.getKey(), e.getEdit());
nextQueue.offer(e);
numberOfFileEntries++;
}
}
if (nextQueue.size() == this.numberOfFileEntries && getFailureType() == FailureType.BEGINNING) {
throw this.addFileInfoToException(new IOException("fake Exception"));
} else if (nextQueue.size() == this.numberOfFileEntries / 2
&& getFailureType() == FailureType.MIDDLE) {
throw this.addFileInfoToException(new IOException("fake Exception"));
} else if (nextQueue.size() == 1 && getFailureType() == FailureType.END) {
throw this.addFileInfoToException(new IOException("fake Exception"));
}
if (nextQueue.peek() != null) {
edit++;
}
Entry e = nextQueue.poll();
if (e.getEdit().isEmpty()) {
return null;
}
return e;
}
/**
* Inserts three waledits in the wal file, and reads them back. The first edit is of a regular
* table, second waledit is for the ROOT table (it will be ignored while reading), and last
* waledit is for the hbase:meta table, which will be linked to the new system:meta table.
*
* @throws IOException
*/
@Test
public void testReadOldRootAndMetaEdits() throws IOException {
LOG.debug("testReadOldRootAndMetaEdits");
Configuration conf = HBaseConfiguration.create();
conf.setClass(
"hbase.regionserver.hlog.writer.impl", SequenceFileLogWriter.class, HLog.Writer.class);
// kv list to be used for all WALEdits.
byte[] row = Bytes.toBytes("row");
KeyValue kv = new KeyValue(row, row, row, row);
List<KeyValue> kvs = new ArrayList<KeyValue>();
kvs.add(kv);
HLog.Writer writer = null;
HLog.Reader reader = null;
// a regular table
TableName t = TableName.valueOf("t");
HRegionInfo tRegionInfo = null;
int logCount = 0;
long timestamp = System.currentTimeMillis();
Path path = new Path(dir, "t");
try {
tRegionInfo = new HRegionInfo(t, HConstants.EMPTY_START_ROW, HConstants.EMPTY_END_ROW);
HLog.Entry tEntry =
createAEntry(
new HLogKey(
tRegionInfo.getEncodedNameAsBytes(),
t,
++logCount,
timestamp,
HConstants.DEFAULT_CLUSTER_ID),
kvs);
// create a old root edit (-ROOT-).
HLog.Entry rootEntry =
createAEntry(
new HLogKey(
Bytes.toBytes(TableName.OLD_ROOT_STR),
TableName.OLD_ROOT_TABLE_NAME,
++logCount,
timestamp,
HConstants.DEFAULT_CLUSTER_ID),
kvs);
// create a old meta edit (hbase:meta).
HLog.Entry oldMetaEntry =
createAEntry(
new HLogKey(
Bytes.toBytes(TableName.OLD_META_STR),
TableName.OLD_META_TABLE_NAME,
++logCount,
timestamp,
HConstants.DEFAULT_CLUSTER_ID),
kvs);
// write above entries
writer = HLogFactory.createWALWriter(fs, path, conf);
writer.append(tEntry);
writer.append(rootEntry);
writer.append(oldMetaEntry);
// sync/close the writer
writer.sync();
writer.close();
// read the log and see things are okay.
reader = HLogFactory.createReader(fs, path, conf);
HLog.Entry entry = reader.next();
assertNotNull(entry);
assertTrue(entry.getKey().getTablename().equals(t));
assertEquals(
Bytes.toString(entry.getKey().getEncodedRegionName()),
Bytes.toString(tRegionInfo.getEncodedNameAsBytes()));
// read the ROOT waledit, but that will be ignored, and hbase:meta waledit will be read
// instead.
entry = reader.next();
assertEquals(entry.getKey().getTablename(), TableName.META_TABLE_NAME);
// should reach end of log
assertNull(reader.next());
} finally {
if (writer != null) {
writer.close();
}
if (reader != null) {
reader.close();
}
}
}
