org.apache.bookkeeper.mledger.offload.jcloud.OffloadIndexBlock Maven / Gradle / Ivy
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* Licensed to the Apache Software Foundation (ASF) under one
* or more contributor license agreements. See the NOTICE file
* distributed with this work for additional information
* regarding copyright ownership. The ASF licenses this file
* to you under the Apache License, Version 2.0 (the
* "License"); you may not use this file except in compliance
* with the License. You may obtain a copy of the License at
*
* http://www.apache.org/licenses/LICENSE-2.0
*
* Unless required by applicable law or agreed to in writing,
* software distributed under the License is distributed on an
* "AS IS" BASIS, WITHOUT WARRANTIES OR CONDITIONS OF ANY
* KIND, either express or implied. See the License for the
* specific language governing permissions and limitations
* under the License.
*/
package org.apache.bookkeeper.mledger.offload.jcloud;
import java.io.Closeable;
import java.io.FilterInputStream;
import java.io.IOException;
import java.io.InputStream;
import org.apache.bookkeeper.client.api.LedgerMetadata;
import org.apache.bookkeeper.common.annotation.InterfaceStability.Unstable;
/**
* The Index block abstraction used for offload a ledger to long term storage.
*/
@Unstable
public interface OffloadIndexBlock extends Closeable, OffloadIndexBlockV2 {
/**
* Get the content of the index block as InputStream.
* Read out in format:
* | index_magic_header | index_block_len | index_entry_count |
* | data_object_size | segment_metadata_length | segment metadata | index entries ... |
*/
IndexInputStream toStream() throws IOException;
/**
* Get the related OffloadIndexEntry that contains the given messageEntryId.
*
* @param messageEntryId
* the entry id of message
* @return the offload index entry
*/
OffloadIndexEntry getIndexEntryForEntry(long messageEntryId) throws IOException;
/**
* Get the entry count that contained in this index Block.
*/
int getEntryCount();
/**
* Get LedgerMetadata.
*/
LedgerMetadata getLedgerMetadata();
/**
* Get the total size of the data object.
*/
long getDataObjectLength();
/**
* Get the length of the header in the blocks in the data object.
*/
long getDataBlockHeaderLength();
/**
* An input stream which knows the size of the stream upfront.
*/
class IndexInputStream extends FilterInputStream {
final long streamSize;
public IndexInputStream(InputStream in, long streamSize) {
super(in);
this.streamSize = streamSize;
}
/**
* @return the number of bytes in the stream.
*/
public long getStreamSize() {
return streamSize;
}
}
default OffloadIndexEntry getIndexEntryForEntry(long ledgerId, long messageEntryId) throws IOException {
return getIndexEntryForEntry(messageEntryId);
}
default long getStartEntryId(long ledgerId) {
return 0; //Offload index block v1 always start with 0;
}
default LedgerMetadata getLedgerMetadata(long ledgerId) {
return getLedgerMetadata();
}
}