1  <dependencies>
 2         <!-- 添加oracle jdbc driver -->
 3         <dependency>
 4             <groupId>cn.easyproject</groupId>
 5             <artifactId>ojdbc6</artifactId>
 6             <version>12.1.0.2.0</version>
 7         </dependency>
 8 
 9         <dependency>
10             <groupId>commons-dbcp</groupId>
11             <artifactId>commons-dbcp</artifactId>
12             <version>1.4</version>
13         </dependency>
14 
15         <dependency>
16             <groupId>c3p0</groupId>
17             <artifactId>c3p0</artifactId>
18             <version>0.9.1.2</version>
19         </dependency>
20 
21         <dependency>
22             <groupId>commons-dbutils</groupId>
23             <artifactId>commons-dbutils</artifactId>
24             <version>1.4</version>
25         </dependency>
26     </dependencies>

/*
create table STUDENT
        (
        id   CHAR(32) not null,
        name VARCHAR2(64)
        )
        */
public class Student {
    private String id;
    private String name;

    public String getId() {
        return id;
    }

    public void setId(String id) {
        this.id = id;
    }

    public String getName() {
        return name;
    }

    public void setName(String name) {
        this.name = name;
    }
}

#连接设置
driverClassName=oracle.jdbc.OracleDriver
url=jdbc:oracle:thin:@127.0.0.1:1521:orcl
username=c##dss
password=123456

#初始化连接
initialSize=10
#最大连接数量
maxActive=20
#最大空闲连接
maxIdle=20
#最小空闲连接
minIdle=5

<c3p0-config>
    <!-- 默认配置，如果没有指定则使用这个配置 -->
    <default-config>
        <property name="driverClass">oracle.jdbc.OracleDriver</property>
        <property name="jdbcUrl">jdbc:oracle:thin:@127.0.0.1:1521:orcl</property>
        <property name="user">c##dss</property>
        <property name="password">123456</property>
        <!-- 初始化池大小 -->
        <property name="initialPoolSize">10</property>
        <!-- 最大空闲时间 -->
        <property name="maxIdleTime">30</property>
        <!-- 最多有多少个连接 -->
        <property name="maxPoolSize">20</property>
        <!-- 最少几个连接 -->
        <property name="minPoolSize">10</property>
        <!-- 每次最多可以执行多少个批处理语句 -->
        <property name="maxStatements">50</property>
    </default-config>
</c3p0-config>

public class DatadbcpUtil {
    private static BasicDataSource dataSource;

    static {
        try {
            InputStream in = DatadbcpUtil.class.getClassLoader().getResourceAsStream("dbcpconfig.properties");
            Properties props = new Properties();
            props.load(in);
            dataSource =(BasicDataSource) BasicDataSourceFactory.createDataSource(props);
        } catch (Exception e) {
            e.printStackTrace();
            throw new ExceptionInInitializerError(e);
        }
    }

    /**
     * 获取DataSource对象
     * @return
     */
    public static BasicDataSource getDataSource() {
        return dataSource;
    }

}

public class DataC3p0Util {
    private static ComboPooledDataSource ds = null;
    static {
        ds = new ComboPooledDataSource();//读取默认配置文件
    }
    public static ComboPooledDataSource getDataSource() {
        return ds;
    }
    public static Connection getConnection() {
        Connection con = null;
        if(con==null) {
            try {
                con = ds.getConnection();
            } catch (SQLException e) {
                e.printStackTrace();
            }
        }
        return con;
    }

}

public class DBCPorC3PO {

    public static void main(String[] arg0) throws Exception {
        int n = 5;
        long startTime = System.currentTimeMillis();
        CountDownLatch latch=new CountDownLatch(n);
        for(int i=0;i<n;i++){
            //Thread t = new Thread (new C3P0Thread("Thread_"+i,latch));
            Thread t = new Thread (new DBCPThread("Thread_"+i,latch));
            t.start ();
        }
        latch.await();
        System.out.println("耗时" + (System.currentTimeMillis() - startTime));
    }
}

class C3P0Thread implements Runnable {
    String name ;
    CountDownLatch latch;
    C3P0Thread(String name,CountDownLatch latch){
        this.name=name;
        this.latch=latch;
    }
    public void run() {
        try {
            System.out.println("运行" + name);
            for(int i = 5; i > 0; i--) {
                QueryRunner queryRunner = new QueryRunner(DataC3p0Util.getDataSource());
                List<Student> list = queryRunner.query("select * from student t", new BeanListHandler<Student>(Student.class));
            }
            latch.countDown();
            System.out.println("结束" + name);
        }catch (Exception e) {
        }
    }
}

class DBCPThread implements Runnable {
    String name ;
    CountDownLatch latch;
    DBCPThread(String name,CountDownLatch latch){
        this.name=name;
        this.latch=latch;
    }
    public void run() {
        try {
            System.out.println("运行" + name);
            for(int i = 5; i > 0; i--) {
                QueryRunner queryRunner = new QueryRunner(DatadbcpUtil.getDataSource());
                List<Student> list = queryRunner.query("select * from student t", new BeanListHandler<Student>(Student.class));
            }
            latch.countDown();
            System.out.println("结束" + name);
        }catch (Exception e) {
        }
    }
}