@Override
public DatasetDescriptor update(String name, DatasetDescriptor descriptor) {
Compatibility.checkDatasetName(name);
Compatibility.checkDescriptor(descriptor);
if (!exists(name)) {
throw new DatasetNotFoundException("Table not found: " + name);
}
Table table = getHcat().getTable(HiveUtils.DEFAULT_DB, name);
HiveUtils.updateTableSchema(table, descriptor);
getHcat().alterTable(table);
return descriptor;
}
@Override
public Map<String, Object> readRow(String tableName, Object keyObject) throws Exception {
if (!(keyObject instanceof Map)
&& !(keyObject instanceof String)
&& !(keyObject instanceof byte[])) {
throw new IllegalArgumentException(
"Unsupported key type - " + keyObject.getClass().getName());
}
Map<String, Object> result;
HCatTable table = hcatClient.getTable("default", tableName);
String hbaseTableName = HiveUtils.getTableName(table);
HTableInterface tableInterface = tableFactory.getTable(hbaseConfiguration, hbaseTableName);
try {
List<HCatFieldSchema> columns = table.getCols();
HCatFieldSchema keyColumn = columns.get(0);
// we use the serializer to build the row key
HiveSerializer serializer = new HiveSerializer(table);
final byte[] rowKey;
if (keyObject instanceof Map) {
rowKey = serializer.serializeHiveType(keyColumn, null, keyObject, 0);
} else if (keyObject instanceof String) {
rowKey = Bytes.toBytes((String) keyObject);
} else {
rowKey = (byte[]) keyObject;
}
Get get = new Get(rowKey);
get.setCacheBlocks(true);
get.setMaxVersions(1);
Result dbResult = tableInterface.get(get);
HiveDeserializer deserializer = new HiveDeserializer(table, dbResult);
result = deserializer.deserialize();
result.put("__rowkey", rowKey);
} finally {
tableInterface.close();
}
return result;
}
@Override
public Collection<String> list() {
Collection<String> tables = getHcat().getAllTables(HiveUtils.DEFAULT_DB);
List<String> readableTables = Lists.newArrayList();
for (String name : tables) {
Table table = getHcat().getTable(HiveUtils.DEFAULT_DB, name);
if (isManaged(table) || isExternal(table)) { // readable table types
try {
// get a descriptor for the table. if this succeeds, it is readable
HiveUtils.descriptorForTable(conf, table);
readableTables.add(name);
} catch (DatasetException e) {
// not a readable table
} catch (IllegalStateException e) {
// not a readable table
} catch (IllegalArgumentException e) {
// not a readable table
} catch (UnsupportedOperationException e) {
// not a readable table
}
}
}
return readableTables;
}