Spring Framework example source code file (ResourceHolderSupport.java)

This example Spring Framework source code file (ResourceHolderSupport.java) is included in the DevDaily.com "Java Source Code Warehouse" project. The intent of this project is to help you "Learn Java by Example" ^TM.

Java - Spring Framework tags/keywords

date, date, illegalstateexception, no, no, resourceholdersupport, transaction, transaction, transactiontimedoutexception, transactiontimedoutexception, util

The Spring Framework ResourceHolderSupport.java source code

/*
 * Copyright 2002-2007 the original author or authors.
 *
 * 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 org.springframework.transaction.support;

import java.util.Date;

import org.springframework.transaction.TransactionTimedOutException;

/**
 * Convenient base class for resource holders.
 *
 * <p>Features rollback-only support for nested transactions.
 * Can expire after a certain number of seconds or milliseconds,
 * to determine transactional timeouts.
 *
 * @author Juergen Hoeller
 * @since 02.02.2004
 * @see org.springframework.jdbc.datasource.DataSourceTransactionManager#doBegin
 * @see org.springframework.jdbc.datasource.DataSourceUtils#applyTransactionTimeout
 */
public abstract class ResourceHolderSupport {

	private boolean synchronizedWithTransaction = false;

	private boolean rollbackOnly = false;

	private Date deadline;

	private int referenceCount = 0;


	/**
	 * Mark the resource as synchronized with a transaction.
	 */
	public void setSynchronizedWithTransaction(boolean synchronizedWithTransaction) {
		this.synchronizedWithTransaction = synchronizedWithTransaction;
	}

	/**
	 * Return whether the resource is synchronized with a transaction.
	 */
	public boolean isSynchronizedWithTransaction() {
		return this.synchronizedWithTransaction;
	}

	/**
	 * Mark the resource transaction as rollback-only.
	 */
	public void setRollbackOnly() {
		this.rollbackOnly = true;
	}

	/**
	 * Return whether the resource transaction is marked as rollback-only.
	 */
	public boolean isRollbackOnly() {
		return this.rollbackOnly;
	}

	/**
	 * Set the timeout for this object in seconds.
	 * @param seconds number of seconds until expiration
	 */
	public void setTimeoutInSeconds(int seconds) {
		setTimeoutInMillis(seconds * 1000);
	}

	/**
	 * Set the timeout for this object in milliseconds.
	 * @param millis number of milliseconds until expiration
	 */
	public void setTimeoutInMillis(long millis) {
		this.deadline = new Date(System.currentTimeMillis() + millis);
	}

	/**
	 * Return whether this object has an associated timeout.
	 */
	public boolean hasTimeout() {
		return (this.deadline != null);
	}

	/**
	 * Return the expiration deadline of this object.
	 * @return the deadline as Date object
	 */
	public Date getDeadline() {
		return this.deadline;
	}

	/**
	 * Return the time to live for this object in seconds.
	 * Rounds up eagerly, e.g. 9.00001 still to 10.
	 * @return number of seconds until expiration
	 * @throws TransactionTimedOutException if the deadline has already been reached
	 */
	public int getTimeToLiveInSeconds() {
		double diff = ((double) getTimeToLiveInMillis()) / 1000;
		int secs = (int) Math.ceil(diff);
		checkTransactionTimeout(secs <= 0);
		return secs;
	}

	/**
	 * Return the time to live for this object in milliseconds.
	 * @return number of millseconds until expiration
	 * @throws TransactionTimedOutException if the deadline has already been reached
	 */
	public long getTimeToLiveInMillis() throws TransactionTimedOutException{
		if (this.deadline == null) {
			throw new IllegalStateException("No timeout specified for this resource holder");
		}
		long timeToLive = this.deadline.getTime() - System.currentTimeMillis();
		checkTransactionTimeout(timeToLive <= 0);
		return timeToLive;
	}

	/**
	 * Set the transaction rollback-only if the deadline has been reached,
	 * and throw a TransactionTimedOutException.
	 */
	private void checkTransactionTimeout(boolean deadlineReached) throws TransactionTimedOutException {
		if (deadlineReached) {
			setRollbackOnly();
			throw new TransactionTimedOutException("Transaction timed out: deadline was " + this.deadline);
		}
	}

	/**
	 * Increase the reference count by one because the holder has been requested
	 * (i.e. someone requested the resource held by it).
	 */
	public void requested() {
		this.referenceCount++;
	}

	/**
	 * Decrease the reference count by one because the holder has been released
	 * (i.e. someone released the resource held by it).
	 */
	public void released() {
		this.referenceCount--;
	}

	/**
	 * Return whether there are still open references to this holder.
	 */
	public boolean isOpen() {
		return (this.referenceCount > 0);
	}

	/**
	 * Clear the transactional state of this resource holder.
	 */
	public void clear() {
		this.synchronizedWithTransaction = false;
		this.rollbackOnly = false;
		this.deadline = null;
	}

	/**
	 * Reset this resource holder - transactional state as well as reference count.
	 */
	public void reset() {
		clear();
		this.referenceCount = 0;
	}

}