Updated XID

git-svn-id: https://svn.apache.org/repos/asf/incubator/qpid/trunk/qpid@568536 13f79535-47bb-0310-9956-ffa450edef68

1 files changed, 268 insertions, 0 deletions

diff --git a/java/common/src/main/java/org/apache/qpidity/dtx/XidImpl.java b/java/common/src/main/java/org/apache/qpidity/dtx/XidImpl.java
new file mode 100644
index 0000000000..224917ade1
--- /dev/null
+++ b/java/common/src/main/java/org/apache/qpidity/dtx/XidImpl.java
@@ -0,0 +1,268 @@
+/* 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.qpidity.dtx;
+
+import org.slf4j.Logger;
+import org.slf4j.LoggerFactory;
+import org.apache.qpidity.QpidException;
+
+import javax.transaction.xa.Xid;
+
+import java.io.*;
+
+/**
+ * Implements javax.transaction.dtx.Xid
+ */
+public class XidImpl implements Xid
+{
+    /**
+     * this session's logger
+     */
+    private static final Logger _logger = LoggerFactory.getLogger(XidImpl.class);
+
+    /**
+     * the transaction branch identifier part of XID as an array of bytes
+     */
+    private byte[] _branchQualifier;
+
+    /**
+     * the format identifier part of the XID.
+     */
+    private int _formatID;
+
+    /**
+     * the global transaction identifier part of XID as an array of bytes.
+     */
+    private byte[] _globalTransactionID;
+
+    //--- Constructors
+
+    /**
+     * Create new Xid.
+     * this is an empty constructor.
+     */
+    public XidImpl()
+    {
+
+    }
+
+    /**
+     * Create a new XidImpl from an existing Xid.
+     * <p> Usefull for casting external Xids
+     *
+     * @param xid Foreign Xid.
+     */
+    public XidImpl(Xid xid)
+    {
+        _branchQualifier = xid.getBranchQualifier();
+        _formatID = xid.getFormatId();
+        _globalTransactionID = xid.getGlobalTransactionId();
+    }
+
+    /**
+     * Create a new Xid.
+     *
+     * @param branchQualifier     The transaction branch identifier part of XID as an array of bytes.
+     * @param format              The format identifier part of the XID.
+     * @param globalTransactionID The global transaction identifier part of XID as an array of bytes.
+     */
+    public XidImpl(byte[] branchQualifier, int format, byte[] globalTransactionID)
+    {
+        _branchQualifier = branchQualifier;
+        _formatID = format;
+        _globalTransactionID = globalTransactionID;
+    }
+
+    /**
+     * Create a new Xid form its String form
+     * 4         1   1        g            b
+     * +---+---+---+---+---+---+---+-  -+---+---+-  -+---+
+     * |   format_id   | g | b |   txn-id   |   br-id    |
+     * +---+---+---+---+---+---+---+-  -+---+---+-  -+---+
+     * 0               4   5   6           6+g         6+g+b
+     * format_id: an implementation specific format identifier
+     * <p/>
+     * gtrid_length: how many bytes of this form the transaction id
+     * <p/>
+     * bqual_length: how many bytes of this form the branch id
+     * <p/>
+     * data: a sequence of octets of at most 128 bytes containing the txn id and the
+     * branch id
+     * <p/>
+     * Note - The sum of the two lengths must equal the length of the data field.
+     *
+     * @param xid an XID STring Form
+     * @throws QpidException If the string does not represent a valid Xid
+     */
+    public XidImpl(String xid) throws QpidException
+    {
+        if (_logger.isDebugEnabled())
+        {
+            _logger.debug("converting string " + xid + " into XidImpl");
+        }
+        try
+        {
+            DataInputStream input = new DataInputStream(new ByteArrayInputStream(xid.getBytes()));
+            _formatID = (int) input.readLong();
+            int g = input.readByte();
+            int b = input.readByte();
+            _globalTransactionID = new byte[g];
+            _branchQualifier = new byte[b];
+            if (input.read(_globalTransactionID, 0, g) != g)
+            {
+                throw new QpidException("Cannot convert the string " + xid + " into an Xid", null, null);
+            }
+            if (input.read(_branchQualifier, 0, b) != b)
+            {
+                throw new QpidException("Cannot convert the string " + xid + " into an Xid", null, null);
+            }
+        }
+        catch (IOException e)
+        {
+            throw new QpidException("cannot convert the string " + xid + " into an Xid", null, e);
+        }
+    }
+
+    //---  Xid interface implementation
+
+    /**
+     * Format identifier. O means the OSI CCR format.
+     *
+     * @return Global transaction identifier.
+     */
+    public byte[] getGlobalTransactionId()
+    {
+        return _globalTransactionID;
+    }
+
+    /**
+     * Obtain the transaction branch identifier part of XID as an array of bytes.
+     *
+     * @return Branch identifier part of XID.
+     */
+    public byte[] getBranchQualifier()
+    {
+        return _branchQualifier;
+    }
+
+    /**
+     * Obtain the format identifier part of the XID.
+     *
+     * @return Format identifier. O means the OSI CCR format.
+     */
+    public int getFormatId()
+    {
+        return _formatID;
+    }
+
+    //--- Object operations
+
+    /**
+     * Indicates whether some other Xid is "equal to" this one.
+     * <p> Two Xids are equal if and only if their three elementary parts are equal
+     *
+     * @param o the object to compare this <code>XidImpl</code> against.
+     * @return true if the <code>XidImpl</code> are equal, false otherwise.
+     */
+    public boolean equals(Object o)
+    {
+        if (this == o)
+        {
+            return true;
+        }
+        if (o instanceof XidImpl)
+        {
+            XidImpl other = (XidImpl) o;
+            if (_formatID == other.getFormatId())
+            {
+                if (_branchQualifier.length == other.getBranchQualifier().length)
+                {
+                    for (int i = 0; i < _branchQualifier.length; i++)
+                    {
+                        if (_branchQualifier[i] != other.getBranchQualifier()[i])
+                        {
+                            return false;
+                        }
+                    }
+                    if (_globalTransactionID.length == other.getGlobalTransactionId().length)
+                    {
+                        for (int i = 0; i < _globalTransactionID.length; i++)
+                        {
+                            if (_globalTransactionID[i] != other.getGlobalTransactionId()[i])
+                            {
+                                return false;
+                            }
+                        }
+                        // everithing is equal
+                        return true;
+                    }
+                }
+            }
+        }
+        return false;
+    }
+
+    //-- Static helper method
+    /**
+     * Convert an Xid into the AMQP String format.
+     * 
+     * 4         1   1        g            b
+     * +---+---+---+---+---+---+---+-  -+---+---+-  -+---+
+     * |   format_id   | g | b |   txn-id   |   br-id    |
+     * +---+---+---+---+---+---+---+-  -+---+---+-  -+---+
+     * 0               4   5   6           6+g         6+g+b
+     * format_id: an implementation specific format identifier
+     * <p/>
+     * gtrid_length: how many bytes of this form the transaction id
+     * <p/>
+     * bqual_length: how many bytes of this form the branch id
+     * <p/>
+     * data: a sequence of octets of at most 128 bytes containing the txn id and the
+     * branch id
+     * <p/>
+     * Note - The sum of the two lengths must equal the length of the data field.
+     *
+     * @param xid an Xid to convert.
+     * @return The String representation of this Xid
+     * @throws QpidException In case of problem when converting this Xid into a string.
+     */
+    public static String convertToString(Xid xid) throws QpidException
+    {
+        if (_logger.isDebugEnabled())
+        {
+            _logger.debug("converting " + xid + " into a String");
+        }
+        try
+        {
+            ByteArrayOutputStream res = new ByteArrayOutputStream();
+            DataOutputStream out = new DataOutputStream(res);
+            out.writeLong(xid.getFormatId());
+            byte[] txId = xid.getGlobalTransactionId();
+            byte[] brId = xid.getBranchQualifier();
+            out.writeByte(txId.length);
+            out.writeByte(brId.length);
+            out.write(txId);
+            out.write(brId);
+            return res.toString();
+        }
+        catch (IOException e)
+        {
+            throw new QpidException("cannot convert the xid " + xid + " into a String", null, e);
+        }
+    }
+}