Java tutorial
/* * Copyright 2010-2013 10gen Inc. * * Licensed 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 com.zjy.mongo.io; import com.mongodb.BasicDBObject; import org.apache.commons.logging.Log; import org.apache.commons.logging.LogFactory; import org.apache.hadoop.io.Writable; import org.bson.BSONCallback; import org.bson.BSONDecoder; import org.bson.BSONEncoder; import org.bson.BasicBSONCallback; import org.bson.BasicBSONDecoder; import org.bson.BasicBSONEncoder; import org.bson.BasicBSONObject; import org.bson.io.BasicOutputBuffer; import org.bson.io.Bits; import java.io.DataInput; import java.io.DataOutput; import java.io.IOException; @SuppressWarnings("deprecation") public class MongoUpdateWritable implements Writable { private static final Log LOG = LogFactory.getLog(MongoUpdateWritable.class); private final BSONEncoder enc = new BasicBSONEncoder(); private BasicBSONObject query; private BasicBSONObject modifiers; private boolean upsert; private boolean multiUpdate; public MongoUpdateWritable() { this(null, null); } public MongoUpdateWritable(final BasicBSONObject query, final BasicBSONObject modifiers, final boolean upsert, final boolean multiUpdate) { this.query = query; this.modifiers = modifiers; this.upsert = upsert; this.multiUpdate = multiUpdate; } public MongoUpdateWritable(final BasicBSONObject query, final BasicBSONObject modifiers) { this(query, modifiers, true, false); } public BasicBSONObject getQuery() { return query; } public BasicBSONObject getModifiers() { return modifiers; } public boolean isUpsert() { return upsert; } public boolean isMultiUpdate() { return multiUpdate; } public void setQuery(final BasicBSONObject query) { this.query = query; } public void setModifiers(final BasicBSONObject modifiers) { this.modifiers = modifiers; } public void setUpsert(final boolean upsert) { this.upsert = upsert; } public void setMultiUpdate(final boolean multiUpdate) { this.multiUpdate = multiUpdate; } /** * /** {@inheritDoc} * * @see Writable#write(DataOutput) */ public void write(final DataOutput out) throws IOException { BasicOutputBuffer buf = new BasicOutputBuffer(); enc.set(buf); enc.putObject(query); enc.done(); enc.set(buf); enc.putObject(modifiers); enc.done(); buf.pipe(new DataOutputOutputStreamAdapter(out)); out.writeBoolean(upsert); out.writeBoolean(multiUpdate); } /** * {@inheritDoc} * * @see Writable#readFields(DataInput) */ public void readFields(final DataInput in) throws IOException { BSONDecoder dec = new BasicBSONDecoder(); BSONCallback cb = new BasicBSONCallback(); // Read the BSON length from the start of the record byte[] l = new byte[4]; try { in.readFully(l); int dataLen = Bits.readInt(l); byte[] data = new byte[dataLen + 4]; System.arraycopy(l, 0, data, 0, 4); in.readFully(data, 4, dataLen - 4); dec.decode(data, cb); query = (BasicBSONObject) cb.get(); in.readFully(l); dataLen = Bits.readInt(l); data = new byte[dataLen + 4]; System.arraycopy(l, 0, data, 0, 4); in.readFully(data, 4, dataLen - 4); dec.decode(data, cb); modifiers = (BasicBSONObject) cb.get(); upsert = in.readBoolean(); multiUpdate = in.readBoolean(); } catch (Exception e) { /* If we can't read another length it's not an error, just return quietly. */ // TODO - Figure out how to gracefully mark this as an empty LOG.info("No Length Header available." + e); query = new BasicDBObject(); modifiers = new BasicDBObject(); } } @Override public boolean equals(final Object obj) { if (obj == null || getClass() != obj.getClass()) { return false; } final MongoUpdateWritable other = (MongoUpdateWritable) obj; if (upsert != other.upsert || multiUpdate != other.multiUpdate) { return false; } if ((query == null && other.query != null) || (other.query == null && query != null) || (!query.equals(other.query))) { return false; } if ((modifiers == null && other.modifiers != null) || (other.modifiers == null && modifiers != null) || (!modifiers.equals(other.modifiers))) { return false; } return true; } @Override public int hashCode() { int hashCode = query.hashCode(); hashCode ^= modifiers.hashCode(); hashCode ^= (upsert ? 1 : 0) << 1; hashCode ^= (multiUpdate ? 1 : 0) << 2; return hashCode; } }