UserTransactionFacade.java

/**
 * Copyright (C) 2012 Stephan Classen
 * Based on guice-perist (Copyright (C) 2010 Google, 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.github.sclassen.guicejpa;

import static com.google.common.base.Preconditions.checkNotNull;

import javax.transaction.HeuristicMixedException;
import javax.transaction.HeuristicRollbackException;
import javax.transaction.NotSupportedException;
import javax.transaction.RollbackException;
import javax.transaction.Status;
import javax.transaction.SystemException;
import javax.transaction.UserTransaction;

/**
 * Facade to the {@link UserTransaction} which wraps all checked exception into runtime exceptions.
 *
 * @author Stephan Classen
 */
class UserTransactionFacade {

  // ---- Members

  private final UserTransaction txn;


  // ---- Constructor

  /**
   * Constructor.
   *
   * @param txn the actual user transaction to facade. Must not be {@code null}.
   */
  UserTransactionFacade(UserTransaction txn) {
    checkNotNull(txn);
    this.txn = txn;
  }


  // ---- Methods

  /**
   * @see {@link UserTransaction#begin()}.
   */
  void begin() {
    try {
      txn.begin();
    }
    catch (NotSupportedException e) {
      throw new RuntimeException("nested transactions are not supported by the user transaction "
          + txn, e);
    }
    catch (SystemException e) {
      throw new RuntimeException("unexpected error occured", e);
    }
  }

  /**
   * @see {@link UserTransaction#commit()}.
   */
  void commit() {
    try {
      txn.commit();
    }
    catch (SecurityException e) {
      throw new RuntimeException("not allowed to commit the transaction", e);
    }
    catch (IllegalStateException e) {
      throw new RuntimeException("no transaction associated with userTransaction", e);
    }
    catch (RollbackException e) {
      throw new RuntimeException("rollback during commit", e);
    }
    catch (HeuristicMixedException e) {
      throw new RuntimeException("heuristic partial rollback during commit", e);
    }
    catch (HeuristicRollbackException e) {
      throw new RuntimeException("heuristic rollback during commit", e);
    }
    catch (SystemException e) {
      throw new RuntimeException("unexpected error occured", e);
    }
  }

  /**
   * @see {@link UserTransaction#rollback()}.
   */
  void rollback() {
    try {
      txn.rollback();
    }
    catch (IllegalStateException e) {
      throw new RuntimeException("no transaction associated with userTransaction", e);
    }
    catch (SecurityException e) {
      throw new RuntimeException("not allowed to rollback the transaction", e);
    }
    catch (SystemException e) {
      throw new RuntimeException("unexpected error occured", e);
    }
  }

  /**
   * @see {@link UserTransaction#setRollbackOnly()}.
   */
  void setRollbackOnly() {
    try {
      txn.setRollbackOnly();
    }
    catch (IllegalStateException e) {
      throw new RuntimeException("no transaction associated with userTransaction", e);
    }
    catch (SystemException e) {
      throw new RuntimeException("unexpected error occured", e);
    }
  }

  /**
   * @see {@link UserTransaction#getStatus()}.
   */
  int getStatus() {
    try {
      int status = txn.getStatus();
      for (int i = 0; Status.STATUS_UNKNOWN == status && i < 5; i++) {
        try {
          Thread.sleep(30L);
        }
        catch (InterruptedException e) {
          // do nothing
        }
        status = txn.getStatus();
      }
      return status;
    }
    catch (SystemException e) {
      throw new RuntimeException("unexpected error occured", e);
    }
  }

  /**
   * @see {@link UserTransaction#setTransactionTimeout(int)}.
   */
  void setTransactionTimeout(int seconds) {
    try {
      txn.setTransactionTimeout(seconds);
    }
    catch (SystemException e) {
      throw new RuntimeException("unexpected error occured", e);
    }
  }
}