Tomcat6 下 MySQL 5.1 數據源配制

2019-11-17 03:49:47

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數據源配制中有一些參數,不太明白,不明白的咱不說.在這說兩種我用過的.

首先在apache-tomcat-6.0.16/lib 路徑下的 MySQL JDBC 5.1 驅動不能少.

第一種是在TomCat 里配制apache-tomcat-6.0.16/conf/context.xml 如下:

Xml代碼
<?xml version='1.0' encoding='utf-8'?>
<Context>
    <Resource name="jdbc/myTest" auth="Container"
        type="javax.sql.DataSource" username="root" passWord=""
        driverClassName="com.mysql.jdbc.Driver"
        url="jdbc:mysql://192.168.0.68:3306/points" />
    <WatchedResource>WEB-INF/web.xml</WatchedResource>
</Context>

<?xml version='1.0' encoding='utf-8'?>
<Context>
<Resource name="jdbc/myTest" auth="Container"
  type="javax.sql.DataSource" username="root" password=""
  driverClassName="com.mysql.jdbc.Driver"
  url="jdbc:mysql://192.168.0.68:3306/points" />
<WatchedResource>WEB-INF/web.xml</WatchedResource>
</Context>
name 是數據源名稱.格式是:"jdbc/數據源名稱"

username,password 不用說了.這里password 密碼為空.

url 和 JDBC 驅動配相同.
http://bizhi.VeVb.com/
第二種是在項目里面配.WebRoot/META-INF/context.xml 中配:

Xml代碼
<?xml version="1.0" encoding="UTF-8"?>
<Context>
    <Resource name="jdbc/test" auth="Container"
        type="javax.sql.DataSource" username="root" password=""
        driverClassName="com.mysql.jdbc.Driver"
        url="jdbc:mysql://192.168.0.68:3306/points" />
</Context>

<?xml version="1.0" encoding="UTF-8"?>
<Context>
<Resource name="jdbc/test" auth="Container"
  type="javax.sql.DataSource" username="root" password=""
  driverClassName="com.mysql.jdbc.Driver"
  url="jdbc:mysql://192.168.0.68:3306/points" />
</Context>和在 Tomcat 里面幾乎一樣. context.xml 要注意是在 META-INF 下新建是自己新建的.

數據源的使用:

Java代碼
list = new ArrayList();
Connection conn = null;
DataSource ds = null;
PReparedStatement pst = null;
ResultSet rst = null;
String sqlStr = "insert into `user`(`userNo`,`userName`) values (?,?)";
try {
    InitialContext ctx = new InitialContext();
    ds = (DataSource) ctx.lookup("java:comp/env/jdbc/test");
    conn = ds.getConnection();
    pst = conn.prepareStatement(sqlStr);
    pst.clearBatch();
    for (int i = 0; i < 4; i++) {
        pst.setString(1, "good " + i);
        pst.setString(2, "isw " + i);
        // 使用batch，將多個sql操作作為一個單元傳輸給數據庫,
        // Hibernate 中 jdbc.batch_size 網上推薦 30
        pst.addBatch();
    }
    pst.executeBatch();
    rst = pst.executeQuery("select * from user");
    // Fetch Size 是設定JDBC的prepareStatement讀取數據的時候每次從數據庫中取出的記錄條數,
    // Hibernate 中 jdbc.fetch_size 網上推薦 50
    rst.setFetchSize(50);
    while (rst.next()) {
        System.out.println(rst.getString(3));
        list.add(rst.getString(3));
    }
} catch (Exception e) {
    e.printStackTrace();
    return ERROR;
} finally {
    try {
        rst.close();
        pst.close();
        conn.close();
    } catch (SQLException e) {
        e.printStackTrace();
    }
}

list = new ArrayList();
Connection conn = null;
DataSource ds = null;
PreparedStatement pst = null;
ResultSet rst = null;
String sqlStr = "insert into `user`(`userNo`,`userName`) values (?,?)";
try {
InitialContext ctx = new InitialContext();
ds = (DataSource) ctx.lookup("java:comp/env/jdbc/test");
conn = ds.getConnection();
pst = conn.prepareStatement(sqlStr);
pst.clearBatch();
for (int i = 0; i < 4; i++) {
  pst.setString(1, "good " + i);
  pst.setString(2, "isw " + i);
  // 使用batch，將多個sql操作作為一個單元傳輸給數據庫,
  // Hibernate 中 jdbc.batch_size 網上推薦 30
  pst.addBatch();
}
pst.executeBatch();
rst = pst.executeQuery("select * from user");
// Fetch Size 是設定JDBC的prepareStatement讀取數據的時候每次從數據庫中取出的記錄條數,
// Hibernate 中 jdbc.fetch_size 網上推薦 50
rst.setFetchSize(50);
while (rst.next()) {
  System.out.println(rst.getString(3));
  list.add(rst.getString(3));
}
} catch (Exception e) {
e.printStackTrace();
return ERROR;
} finally {
try {
  rst.close();
  pst.close();
  conn.close();
} catch (SQLException e) {
  e.printStackTrace();
}
}    上面說一下,大家都說Hibernate 執行數據庫操作要比手動JDBC 效率要高,這是因為它對查詢進行了一些優化,Fetch Size,Batch 也許只是冰山一角.說到這里就提了一下它們的用法.

關于 Fectch Size,Batch 下面的博客給出較詳細的說明.

http://xuganggogo.javaeye.com/blog/440516

數據源在Hibernate 中的使用 hibernate.cfg.xml

Xml代碼
<?xml version='1.0' encoding='UTF-8'?>
<!DOCTYPE hibernate-configuration PUBLIC
          "-//Hibernate/Hibernate Configuration DTD 3.0//EN"
          "

<hibernate-configuration>
    <session-factory>
                
        <property name="connection.datasource">
            java:comp/env/jdbc/test
        </property>
                
        <property name="dialect">
            org.hibernate.dialect.MySQLDialect
        </property>
        <property name="jdbc.batch_size">25</property>
        <property name="jdbc.fetch_size">50</property>
        <mapping resource="com/isw2/entity/UserBean.hbm.xml" />
    </session-factory>
</hibernate-configuration>