io.druid.data.input.thrift.ThriftDeserialization.java Source code

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Here is the source code for io.druid.data.input.thrift.ThriftDeserialization.java

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/*
 * Licensed to Metamarkets Group Inc. (Metamarkets) under one
 * or more contributor license agreements. See the NOTICE file
 * distributed with this work for additional information
 * regarding copyright ownership. Metamarkets 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 io.druid.data.input.thrift;

import com.google.common.base.Preconditions;
import org.apache.commons.codec.binary.Base64;
import org.apache.thrift.TBase;
import org.apache.thrift.TDeserializer;
import org.apache.thrift.TException;
import org.apache.thrift.TSerializer;
import org.apache.thrift.protocol.TBinaryProtocol;
import org.apache.thrift.protocol.TCompactProtocol;
import org.apache.thrift.protocol.TJSONProtocol;
import org.apache.thrift.protocol.TProtocolFactory;
import org.apache.thrift.protocol.TProtocolUtil;
import org.apache.thrift.protocol.TSimpleJSONProtocol;
import org.slf4j.Logger;
import org.slf4j.LoggerFactory;

public class ThriftDeserialization {
    private static final Logger log = LoggerFactory.getLogger(ThriftDeserialization.class);

    private static final ThreadLocal<TDeserializer> DESERIALIZER_COMPACT = new ThreadLocal<TDeserializer>() {
        @Override
        protected TDeserializer initialValue() {
            return new TDeserializer(new TCompactProtocol.Factory());
        }
    };

    private static final ThreadLocal<TDeserializer> DESERIALIZER_BINARY = new ThreadLocal<TDeserializer>() {
        @Override
        protected TDeserializer initialValue() {
            return new TDeserializer(new TBinaryProtocol.Factory());
        }
    };

    private static final ThreadLocal<TDeserializer> DESERIALIZER_JSON = new ThreadLocal<TDeserializer>() {
        @Override
        protected TDeserializer initialValue() {
            return new TDeserializer(new TJSONProtocol.Factory());
        }
    };

    public static final ThreadLocal<TSerializer> SERIALIZER_SIMPLE_JSON = new ThreadLocal<TSerializer>() {
        @Override
        protected TSerializer initialValue() {
            return new TSerializer(new TSimpleJSONProtocol.Factory());
        }
    };

    private static final byte[] EMPTY_BYTES = new byte[0];

    public static byte[] decodeB64IfNeeded(final byte[] src) {
        Preconditions.checkNotNull(src, "src bytes cannot be null");
        if (src.length <= 0) {
            return EMPTY_BYTES;
        }
        final byte last = src[src.length - 1];
        return (0 == last || '}' == last) ? src : Base64.decodeBase64(src);
    }

    /**
     * Deserializes byte-array into thrift object.
     * <p>
     * Supporting binary, compact and json protocols,
     * and the byte array could be or not be encoded by Base64.
     *
     * @param bytes     the byte-array to deserialize
     * @param thriftObj the output thrift object
     *
     * @return the output thrift object, or null if error occurs
     */
    public static <T extends TBase> T detectAndDeserialize(final byte[] bytes, final T thriftObj)
            throws TException {
        Preconditions.checkNotNull(thriftObj);
        try {
            final byte[] src = decodeB64IfNeeded(bytes);
            final TProtocolFactory protocolFactory = TProtocolUtil.guessProtocolFactory(src, null);
            Preconditions.checkNotNull(protocolFactory);
            if (protocolFactory instanceof TCompactProtocol.Factory) {
                DESERIALIZER_COMPACT.get().deserialize(thriftObj, src);
            } else if (protocolFactory instanceof TBinaryProtocol.Factory) {
                DESERIALIZER_BINARY.get().deserialize(thriftObj, src);
            } else {
                DESERIALIZER_JSON.get().deserialize(thriftObj, src);
            }
        } catch (final IllegalArgumentException e) {
            throw new TException(e);
        }
        return thriftObj;
    }
}