@Override
public Set<Object> loadAllKeys(Set<Object> keysToExclude) throws CacheLoaderException {
Cassandra.Client cassandraClient = null;
try {
cassandraClient = dataSource.getConnection();
Set<Object> s = new HashSet<Object>();
SlicePredicate slicePredicate = new SlicePredicate();
slicePredicate.setSlice_range(
new SliceRange(
ByteBuffer.wrap(entryColumnPath.getColumn()),
ByteBufferUtil.EMPTY_BYTE_BUFFER,
false,
1));
String startKey = "";
boolean complete = false;
// Get the keys in SLICE_SIZE blocks
while (!complete) {
KeyRange keyRange = new KeyRange(SLICE_SIZE);
keyRange.setStart_token(startKey);
keyRange.setEnd_token("");
List<KeySlice> keySlices =
cassandraClient.get_range_slices(
entryColumnParent, slicePredicate, keyRange, readConsistencyLevel);
if (keySlices.size() < SLICE_SIZE) {
complete = true;
} else {
startKey = new String(keySlices.get(keySlices.size() - 1).getKey(), UTF8Charset);
}
for (KeySlice keySlice : keySlices) {
if (keySlice.getColumnsSize() > 0) {
Object key = unhashKey(keySlice.getKey());
if (key != null && (keysToExclude == null || !keysToExclude.contains(key))) s.add(key);
}
}
}
return s;
} catch (Exception e) {
throw new CacheLoaderException(e);
} finally {
dataSource.releaseConnection(cassandraClient);
}
}
@Override
public void clear() throws CacheLoaderException {
Cassandra.Client cassandraClient = null;
try {
cassandraClient = dataSource.getConnection();
SlicePredicate slicePredicate = new SlicePredicate();
slicePredicate.setSlice_range(
new SliceRange(
ByteBuffer.wrap(entryColumnPath.getColumn()),
ByteBufferUtil.EMPTY_BYTE_BUFFER,
false,
1));
String startKey = "";
boolean complete = false;
// Get the keys in SLICE_SIZE blocks
while (!complete) {
KeyRange keyRange = new KeyRange(SLICE_SIZE);
keyRange.setStart_token(startKey);
keyRange.setEnd_token("");
List<KeySlice> keySlices =
cassandraClient.get_range_slices(
entryColumnParent, slicePredicate, keyRange, readConsistencyLevel);
if (keySlices.size() < SLICE_SIZE) {
complete = true;
} else {
startKey = new String(keySlices.get(keySlices.size() - 1).getKey(), UTF8Charset);
}
Map<ByteBuffer, Map<String, List<Mutation>>> mutationMap =
new HashMap<ByteBuffer, Map<String, List<Mutation>>>();
for (KeySlice keySlice : keySlices) {
remove0(ByteBuffer.wrap(keySlice.getKey()), mutationMap);
}
cassandraClient.batch_mutate(mutationMap, ConsistencyLevel.ALL);
}
} catch (Exception e) {
throw new CacheLoaderException(e);
} finally {
dataSource.releaseConnection(cassandraClient);
}
}
public static void main(String[] args) throws UnsupportedEncodingException,
InvalidRequestException, UnavailableException, TimedOutException,
TException, NotFoundException {
TTransport tr = new TSocket(“192.168.1.204″, 9160);
TProtocol proto = new TBinaryProtocol(tr);
Cassandra.Client client = new Cassandra.Client(proto);
tr.open();
String keyspace = “Historical_Info”;
String columnFamily = “Historical_Info_Column”;
//String keyUserID = “3”;
// read entire row
SlicePredicate predicate = new SlicePredicate();
SliceRange sliceRange = new SliceRange();
sliceRange.setStart(new byte[0]);
sliceRange.setFinish(new byte[0]);
predicate.setSlice_range(sliceRange);
KeyRange keyrRange = new KeyRange();
keyrRange.setStart_key(“1″);
keyrRange.setEnd_key(“”);
//keyrRange.setCount(100);
ColumnParent parent = new ColumnParent(columnFamily);
List < KeySlice > ls = client.get_range_slices(keyspace, parent, predicate, keyrRange, ConsistencyLevel.ONE);
for (KeySlice result: ls) {
List < ColumnOrSuperColumn > column = result.columns;
for (ColumnOrSuperColumn result2: column) {
Column column2 = result2.column;
System.out.println(new String(column2.name, UTF8) + ” - > ” + new String(column2.value, UTF8));
}
}
tr.close();
}
/**
* Perform a range scan for a set of records in the database. Each field/value pair from the
* result will be stored in a HashMap.
*
* @param table The name of the table
* @param startkey The record key of the first record to read.
* @param recordcount The number of records to read
* @param fields The list of fields to read, or null for all of them
* @param result A Vector of HashMaps, where each HashMap is a set field/value pairs for one
* record
* @return Zero on success, a non-zero error code on error
*/
public int scan(
String table,
String startkey,
int recordcount,
Set<String> fields,
Vector<HashMap<String, ByteIterator>> result) {
if (!_table.equals(table)) {
try {
client.set_keyspace(table);
_table = table;
} catch (Exception e) {
e.printStackTrace();
e.printStackTrace(System.out);
return Error;
}
}
for (int i = 0; i < OperationRetries; i++) {
try {
SlicePredicate predicate;
if (fields == null) {
predicate =
new SlicePredicate()
.setSlice_range(new SliceRange(emptyByteBuffer, emptyByteBuffer, false, 1000000));
} else {
ArrayList<ByteBuffer> fieldlist = new ArrayList<ByteBuffer>(fields.size());
for (String s : fields) {
fieldlist.add(ByteBuffer.wrap(s.getBytes("UTF-8")));
}
predicate = new SlicePredicate().setColumn_names(fieldlist);
}
KeyRange kr =
new KeyRange()
.setStart_key(startkey.getBytes("UTF-8"))
.setEnd_key(new byte[] {})
.setCount(recordcount);
List<KeySlice> results =
client.get_range_slices(parent, predicate, kr, ConsistencyLevel.ONE);
if (_debug) {
System.out.println("Scanning startkey: " + startkey);
}
HashMap<String, ByteIterator> tuple;
for (KeySlice oneresult : results) {
tuple = new HashMap<String, ByteIterator>();
Column column;
String name;
ByteIterator value;
for (ColumnOrSuperColumn onecol : oneresult.columns) {
column = onecol.column;
name =
new String(
column.name.array(),
column.name.position() + column.name.arrayOffset(),
column.name.remaining());
value =
new ByteArrayByteIterator(
column.value.array(),
column.value.position() + column.value.arrayOffset(),
column.value.remaining());
tuple.put(name, value);
if (_debug) {
System.out.print("(" + name + "=" + value + ")");
}
}
result.add(tuple);
if (_debug) {
System.out.println();
}
}
return Ok;
} catch (Exception e) {
errorexception = e;
}
try {
Thread.sleep(500);
} catch (InterruptedException e) {
}
}
errorexception.printStackTrace();
errorexception.printStackTrace(System.out);
return Error;
}
@Override
public Set<InternalCacheEntry> load(int numEntries) throws CacheLoaderException {
Cassandra.Client cassandraClient = null;
try {
cassandraClient = dataSource.getConnection();
Set<InternalCacheEntry> s = new HashSet<InternalCacheEntry>();
SlicePredicate slicePredicate = new SlicePredicate();
slicePredicate.setSlice_range(
new SliceRange(
ByteBuffer.wrap(entryColumnPath.getColumn()),
ByteBufferUtil.EMPTY_BYTE_BUFFER,
false,
1));
String startKey = "";
// Get the keys in SLICE_SIZE blocks
int sliceSize = Math.min(SLICE_SIZE, numEntries);
for (boolean complete = false; !complete; ) {
KeyRange keyRange = new KeyRange(sliceSize);
keyRange.setStart_token(startKey);
keyRange.setEnd_token("");
List<KeySlice> keySlices =
cassandraClient.get_range_slices(
entryColumnParent, slicePredicate, keyRange, readConsistencyLevel);
// Cycle through all the keys
for (KeySlice keySlice : keySlices) {
Object key = unhashKey(keySlice.getKey());
if (key == null) // Skip invalid keys
continue;
List<ColumnOrSuperColumn> columns = keySlice.getColumns();
if (columns.size() > 0) {
if (log.isDebugEnabled()) {
log.debugf("Loading %s", key);
}
byte[] value = columns.get(0).getColumn().getValue();
InternalCacheEntry ice = unmarshall(value, key);
s.add(ice);
} else if (log.isDebugEnabled()) {
log.debugf("Skipping empty key %s", key);
}
}
if (keySlices.size() < sliceSize) {
// Cassandra has returned less keys than what we asked for.
// Assume we have finished
complete = true;
} else {
// Cassandra has returned exactly the amount of keys we
// asked for. If we haven't reached the required quota yet,
// assume we need to cycle again starting from
// the last returned key (excluded)
sliceSize = Math.min(SLICE_SIZE, numEntries - s.size());
if (sliceSize == 0) {
complete = true;
} else {
startKey = new String(keySlices.get(keySlices.size() - 1).getKey(), UTF8Charset);
}
}
}
return s;
} catch (Exception e) {
throw new CacheLoaderException(e);
} finally {
dataSource.releaseConnection(cassandraClient);
}
}
