Subversion Repositories SmartDukaan

/**

 * 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.thrift;

import java.util.ArrayList;

import java.util.HashMap;

import java.util.HashSet;

import java.util.List;

import java.util.Map;

import java.util.Set;

import org.apache.thrift.protocol.TField;

import org.apache.thrift.protocol.TProtocol;

import org.apache.thrift.protocol.TProtocolException;

import org.apache.thrift.protocol.TStruct;

public abstract class TUnion<F extends TFieldIdEnum> implements TBase<F> {

  protected Object value_;

  protected F setField_;

  protected TUnion() {

    setField_ = null;

    value_ = null;

  }

  protected TUnion(F setField, Object value) {

    setFieldValue(setField, value);

  }

  protected TUnion(TUnion<F> other) {

    if (!other.getClass().equals(this.getClass())) {

      throw new ClassCastException();

    }

    setField_ = other.setField_;

    value_ = deepCopyObject(other.value_);

  }

  private static Object deepCopyObject(Object o) {

    if (o instanceof TBase) {

      return ((TBase)o).deepCopy();

    } else if (o instanceof byte[]) {

      byte[] other_val = (byte[])o;

      byte[] this_val = new byte[other_val.length];

      System.arraycopy(other_val, 0, this_val, 0, other_val.length);

      return this_val;

    } else if (o instanceof List) {

      return deepCopyList((List)o);

    } else if (o instanceof Set) {

      return deepCopySet((Set)o);

    } else if (o instanceof Map) {

      return deepCopyMap((Map)o);

    } else {

      return o;

    }

  }

  private static Map deepCopyMap(Map<Object, Object> map) {

    Map copy = new HashMap();

    for (Map.Entry<Object, Object> entry : map.entrySet()) {

      copy.put(deepCopyObject(entry.getKey()), deepCopyObject(entry.getValue()));

    }

    return copy;

  }

  private static Set deepCopySet(Set set) {

    Set copy = new HashSet();

    for (Object o : set) {

      copy.add(deepCopyObject(o));

    }

    return copy;

  }

  private static List deepCopyList(List list) {

    List copy = new ArrayList(list.size());

    for (Object o : list) {

      copy.add(deepCopyObject(o));

    }

    return copy;

  }

  public F getSetField() {

    return setField_;

  }

  public Object getFieldValue() {

    return value_;

  }

  public Object getFieldValue(F fieldId) {

    if (fieldId != setField_) {

      throw new IllegalArgumentException("Cannot get the value of field " + fieldId + " because union's set field is " + setField_);

    }

    return getFieldValue();

  }

  public Object getFieldValue(int fieldId) {

    return getFieldValue(enumForId((short)fieldId));

  }

  public boolean isSet() {

    return setField_ != null;

  }

  public boolean isSet(F fieldId) {

    return setField_ == fieldId;

  }

  public boolean isSet(int fieldId) {

    return isSet(enumForId((short)fieldId));

  }

  public void read(TProtocol iprot) throws TException {

    setField_ = null;

    value_ = null;

    iprot.readStructBegin();

    TField field = iprot.readFieldBegin();

    value_ = readValue(iprot, field);

    if (value_ != null) {

      setField_ = enumForId(field.id);

    }

    iprot.readFieldEnd();

    // this is so that we will eat the stop byte. we could put a check here to

    // make sure that it actually *is* the stop byte, but it's faster to do it

    // this way.

    iprot.readFieldBegin();

    iprot.readStructEnd();

  }

  public void setFieldValue(F fieldId, Object value) {

    checkType(fieldId, value);

    setField_ = fieldId;

    value_ = value;

  }

  public void setFieldValue(int fieldId, Object value) {

    setFieldValue(enumForId((short)fieldId), value);

  }

  public void write(TProtocol oprot) throws TException {

    if (getSetField() == null || getFieldValue() == null) {

      throw new TProtocolException("Cannot write a TUnion with no set value!");

    }

    oprot.writeStructBegin(getStructDesc());

    oprot.writeFieldBegin(getFieldDesc(setField_));

    writeValue(oprot, setField_, value_);

    oprot.writeFieldEnd();

    oprot.writeFieldStop();

    oprot.writeStructEnd();

  }

  /**

   * Implementation should be generated so that we can efficiently type check 

   * various values.

   * @param setField

   * @param value

   */

  protected abstract void checkType(F setField, Object value) throws ClassCastException;

  /**

   * Implementation should be generated to read the right stuff from the wire 

   * based on the field header. 

   * @param field

   * @return

   */

  protected abstract Object readValue(TProtocol iprot, TField field) throws TException;

  protected abstract void writeValue(TProtocol oprot, F setField, Object value) throws TException;

  protected abstract TStruct getStructDesc();

  protected abstract TField getFieldDesc(F setField);

  protected abstract F enumForId(short id);

  @Override

  public String toString() {

    Object v = getFieldValue();

    String vStr = null;

    if (v instanceof byte[]) {

      vStr = bytesToStr((byte[])v);

    } else {

      vStr = v.toString();

    }

    return "<" + this.getClass().getSimpleName() + " " + getFieldDesc(getSetField()).name + ":" + vStr + ">";

  }

  private static String bytesToStr(byte[] bytes) {

    StringBuilder sb = new StringBuilder();

    int size = Math.min(bytes.length, 128);

    for (int i = 0; i < size; i++) {

      if (i != 0) {

        sb.append(" ");

      }

      String digit = Integer.toHexString(bytes[i]);

      sb.append(digit.length() > 1 ? digit : "0" + digit);

    }

    if (bytes.length > 128) {

      sb.append(" ...");

    }

    return sb.toString();

  }

}