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MyBatis官方文档

• ORM框架

源码

package org.apache.ibatis.datasource.pooled;import java.util.ArrayList;import java.util.List;/** * @author Clinton Begin */public class PoolState {
     protected PooledDataSource dataSource;  protected final List
   
     idleConnections = new ArrayList
    
     ();  protected final List
     
       activeConnections = new ArrayList
      
       ();  protected long requestCount = 0;  protected long accumulatedRequestTime = 0;  protected long accumulatedCheckoutTime = 0;  protected long claimedOverdueConnectionCount = 0;  protected long accumulatedCheckoutTimeOfOverdueConnections = 0;  protected long accumulatedWaitTime = 0;  protected long hadToWaitCount = 0;  protected long badConnectionCount = 0;  public PoolState(PooledDataSource dataSource) {
       this.dataSource = dataSource;  }  public synchronized long getRequestCount() {
       return requestCount;  }/** * 条件表达式,避免了ArithmeticException异常 * synchronized实现了方法级别的线程安全 */  public synchronized long getAverageRequestTime() {
       return requestCount == 0 ? 0 : accumulatedRequestTime / requestCount;  }  public synchronized long getAverageWaitTime() {
       return hadToWaitCount == 0 ? 0 : accumulatedWaitTime / hadToWaitCount;  }  public synchronized long getHadToWaitCount() {
       return hadToWaitCount;  }  public synchronized long getBadConnectionCount() {
       return badConnectionCount;  }  public synchronized long getClaimedOverdueConnectionCount() {
       return claimedOverdueConnectionCount;  }  public synchronized long getAverageOverdueCheckoutTime() {
       return claimedOverdueConnectionCount == 0 ? 0 : accumulatedCheckoutTimeOfOverdueConnections / claimedOverdueConnectionCount;  }  public synchronized long getAverageCheckoutTime() {
       return requestCount == 0 ? 0 : accumulatedCheckoutTime / requestCount;  }  public synchronized int getIdleConnectionCount() {
       return idleConnections.size();  }  public synchronized int getActiveConnectionCount() {
       return activeConnections.size();  }/** * 日志排版格式很好 * synchronized 保证了方法级别的线程安全 * StringBuilder 线程不安全 */  @Override  public synchronized String toString() {
       StringBuilder builder = new StringBuilder();    builder.append("\n===CONFINGURATION==============================================");    builder.append("\n jdbcDriver                     ").append(dataSource.getDriver());    builder.append("\n jdbcUrl                        ").append(dataSource.getUrl());    builder.append("\n jdbcUsername                   ").append(dataSource.getUsername());    builder.append("\n jdbcPassword                   ").append((dataSource.getPassword() == null ? "NULL" : "************"));    builder.append("\n poolMaxActiveConnections       ").append(dataSource.poolMaximumActiveConnections);    builder.append("\n poolMaxIdleConnections         ").append(dataSource.poolMaximumIdleConnections);    builder.append("\n poolMaxCheckoutTime            ").append(dataSource.poolMaximumCheckoutTime);    builder.append("\n poolTimeToWait                 ").append(dataSource.poolTimeToWait);    builder.append("\n poolPingEnabled                ").append(dataSource.poolPingEnabled);    builder.append("\n poolPingQuery                  ").append(dataSource.poolPingQuery);    builder.append("\n poolPingConnectionsNotUsedFor  ").append(dataSource.poolPingConnectionsNotUsedFor);    builder.append("\n ---STATUS-----------------------------------------------------");    builder.append("\n activeConnections              ").append(getActiveConnectionCount());    builder.append("\n idleConnections                ").append(getIdleConnectionCount());    builder.append("\n requestCount                   ").append(getRequestCount());    builder.append("\n averageRequestTime             ").append(getAverageRequestTime());    builder.append("\n averageCheckoutTime            ").append(getAverageCheckoutTime());    builder.append("\n claimedOverdue                 ").append(getClaimedOverdueConnectionCount());    builder.append("\n averageOverdueCheckoutTime     ").append(getAverageOverdueCheckoutTime());    builder.append("\n hadToWait                      ").append(getHadToWaitCount());    builder.append("\n averageWaitTime                ").append(getAverageWaitTime());    builder.append("\n badConnectionCount             ").append(getBadConnectionCount());    builder.append("\n===============================================================");    return builder.toString();  }}
      
     
    
   

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