add xa support

src/main/java/com/alibaba/druid/pool/DruidDataSource.java

@@ -375,9 +375,7 @@ public class DruidDataSource extends DruidAbstractDataSource implements DruidDat
                 this.dbType = JdbcUtils.getDbType(jdbcUrl, driverClass.getClass().getName());
             }
 
-            if ("oracle".equals(this.dbType)) {
-                initOracle();
-            }
+            initCheck();
 
             initExceptionSorter();
             initValidConnectionChecker();
@@ -510,16 +508,18 @@ public class DruidDataSource extends DruidAbstractDataSource implements DruidDat
         LOG.error(errorMessage + "validationQuery not set");
     }
 
-    protected void initOracle() throws SQLException {
-        isOracle = true;
+    protected void initCheck() throws SQLException {
+        if (JdbcUtils.ORACLE.equals(this.dbType)) {
+            isOracle = true;
 
-        if (driver.getMajorVersion() < 10) {
-            throw new SQLException("not support oracle driver " + driver.getMajorVersion() + "."
-                                   + driver.getMinorVersion());
-        }
+            if (driver.getMajorVersion() < 10) {
+                throw new SQLException("not support oracle driver " + driver.getMajorVersion() + "."
+                                       + driver.getMinorVersion());
+            }
 
-        if (driver.getMajorVersion() == 10 && isUseOracleImplicitCache()) {
-            this.getConnectProperties().setProperty("oracle.jdbc.FreeMemoryOnEnterImplicitCache", "true");
+            if (driver.getMajorVersion() == 10 && isUseOracleImplicitCache()) {
+                this.getConnectProperties().setProperty("oracle.jdbc.FreeMemoryOnEnterImplicitCache", "true");
+            }
         }
     }
 

src/main/java/com/alibaba/druid/pool/xa/DruidXADataSource.java

@@ -11,40 +11,62 @@ import com.alibaba.druid.pool.DruidDataSource;
 import com.alibaba.druid.pool.DruidPooledConnection;
 import com.alibaba.druid.support.logging.Log;
 import com.alibaba.druid.support.logging.LogFactory;
+import com.alibaba.druid.util.H2Utils;
 import com.alibaba.druid.util.JdbcUtils;
 import com.alibaba.druid.util.MySqlUtils;
 import com.alibaba.druid.util.OracleUtils;
 import com.alibaba.druid.util.PGUtils;
 
-public class DruidAXDataSource extends DruidDataSource implements XADataSource {
+public class DruidXADataSource extends DruidDataSource implements XADataSource {
 
-    private final static Log  LOG              = LogFactory.getLog(DruidAXDataSource.class);
+    private final static Log  LOG              = LogFactory.getLog(DruidXADataSource.class);
 
     private static final long serialVersionUID = 1L;
 
+    private Object            h2Factory        = null;
+
     @Override
     public XAConnection getXAConnection() throws SQLException {
         DruidPooledConnection conn = this.getConnection();
 
         Connection physicalConn = conn.unwrap(Connection.class);
 
-        XAConnection rawXAConnection;
+        XAConnection rawXAConnection = createPhysicalXAConnetion(physicalConn);
+
+        return new DruidPooledXAConnection(conn, rawXAConnection);
+    }
+
+    protected void initCheck() throws SQLException {
+        super.initCheck();
+
+        if (JdbcUtils.H2.equals(this.dbType)) {
+            h2Factory = H2Utils.createJdbcDataSourceFactory();
+        }
+    }
+
+    private XAConnection createPhysicalXAConnetion(Connection physicalConn) throws SQLException {
         if (JdbcUtils.ORACLE.equals(dbType)) {
             try {
-                rawXAConnection = OracleUtils.OracleXAConnection(physicalConn);
+                return OracleUtils.OracleXAConnection(physicalConn);
             } catch (XAException xae) {
                 LOG.error("create xaConnection error", xae);
                 return null;
             }
-        } else if (JdbcUtils.MYSQL.equals(dbType)) {
-            rawXAConnection = MySqlUtils.createXAConnection(physicalConn);
-        } else if (JdbcUtils.POSTGRESQL.equals(dbType)) {
-            rawXAConnection = PGUtils.createXAConnection(physicalConn);
-        } else {
-            throw new SQLException("xa not support dbType : " + this.dbType);
         }
 
-        return new DruidPooledXAConnection(conn, rawXAConnection);
+        if (JdbcUtils.MYSQL.equals(dbType)) {
+            return MySqlUtils.createXAConnection(physicalConn);
+        }
+
+        if (JdbcUtils.POSTGRESQL.equals(dbType)) {
+            return PGUtils.createXAConnection(physicalConn);
+        }
+
+        if (JdbcUtils.H2.equals(dbType)) {
+            return H2Utils.createXAConnection(h2Factory, physicalConn);
+        }
+
+        throw new SQLException("xa not support dbType : " + this.dbType);
     }
 
     @Override

src/main/java/com/alibaba/druid/util/H2Utils.java

@@ -0,0 +1,52 @@
+package com.alibaba.druid.util;
+
+import java.lang.reflect.Constructor;
+import java.lang.reflect.Method;
+import java.sql.Connection;
+import java.sql.SQLException;
+
+import javax.sql.XAConnection;
+
+import org.h2.jdbc.JdbcConnection;
+import org.h2.jdbcx.JdbcDataSourceFactory;
+import org.h2.jdbcx.JdbcXAConnection;
+import org.h2.message.TraceObject;
+
+public class H2Utils {
+
+    private static volatile Constructor<JdbcXAConnection> constructor;
+
+    private static volatile Method                        method;
+
+    public static final int                               XA_DATA_SOURCE = 13;
+
+    public static Object createJdbcDataSourceFactory() {
+        return new JdbcDataSourceFactory();
+    }
+
+    public static XAConnection createXAConnection(Object factory, Connection physicalConn) throws SQLException {
+
+        try {
+            if (constructor == null) {
+                constructor = JdbcXAConnection.class.getConstructor(JdbcDataSourceFactory.class, int.class,
+                                                                    JdbcConnection.class);
+                constructor.setAccessible(true);
+            }
+
+            int id = getNextId(XA_DATA_SOURCE);
+
+            return constructor.newInstance(factory, id, physicalConn);
+        } catch (Exception e) {
+            throw new SQLException("createXAConnection error", e);
+        }
+    }
+
+    public static int getNextId(int type) throws Exception {
+        if (method == null) {
+            method = TraceObject.class.getMethod("getNextId", int.class);
+            method.setAccessible(true);
+        }
+
+        return (Integer) method.invoke(null, type);
+    }
+}

src/main/java/com/alibaba/druid/util/MySqlUtils.java

@@ -3,11 +3,13 @@ package com.alibaba.druid.util;
 import java.sql.Connection;
 import java.sql.SQLException;
 
+import javax.sql.XAConnection;
+
 import com.mysql.jdbc.jdbc2.optional.MysqlXAConnection;
 
 public class MySqlUtils {
 
-    public static MysqlXAConnection createXAConnection(Connection physicalConn) throws SQLException {
+    public static XAConnection createXAConnection(Connection physicalConn) throws SQLException {
         return new MysqlXAConnection((com.mysql.jdbc.ConnectionImpl) physicalConn, false);
     }
 }

src/main/java/com/alibaba/druid/util/OracleUtils.java

@@ -5,6 +5,7 @@ import java.sql.PreparedStatement;
 import java.sql.ResultSet;
 import java.sql.SQLException;
 
+import javax.sql.XAConnection;
 import javax.transaction.xa.XAException;
 
 import oracle.jdbc.OracleConnection;
@@ -19,7 +20,7 @@ import com.alibaba.druid.pool.DruidPooledPreparedStatement;
 
 public class OracleUtils {
 
-    public static OracleXAConnection OracleXAConnection(Connection oracleConnection) throws XAException {
+    public static XAConnection OracleXAConnection(Connection oracleConnection) throws XAException {
         return new OracleXAConnection(oracleConnection);
     }
 

src/main/java/com/alibaba/druid/util/PGUtils.java

@@ -3,12 +3,14 @@ package com.alibaba.druid.util;
 import java.sql.Connection;
 import java.sql.SQLException;
 
+import javax.sql.XAConnection;
+
 import org.postgresql.core.BaseConnection;
 import org.postgresql.xa.PGXAConnection;
 
 public class PGUtils {
 
-    public static PGXAConnection createXAConnection(Connection physicalConn) throws SQLException {
+    public static XAConnection createXAConnection(Connection physicalConn) throws SQLException {
         return new PGXAConnection((BaseConnection) physicalConn);
     }
 }