Java Web Commons-Utils (数据库连接方法)
新建java project项目;
Build Path;
commons-dbutils-1.3.jar
数据库驱动类:Oracle: ojdbc6.jar MySQL: mysql-connector-java-5.1.7-bin.jar
MapListExample.java
代码:
package webbook.chapter5;
import org.apache.commons.dbutils.DbUtils;
import org.apache.commons.dbutils.QueryRunner;
import org.apache.commons.dbutils.handlers.MapListHandler;
import java.sql.Connection;
import java.sql.DriverManager;
import java.sql.SQLException;
import java.util.List;
import java.util.Map;
public class MapListExample {
public static void main(String[] args) {
Connection conn = null;
String url = "jdbc:oracle:thin:@192.168.1.20:1521:ora9";
String jdbcDriver = "oracle.jdbc.driver.OracleDriver";
String user = "scott";
String password = "tiger";
DbUtils.loadDriver(jdbcDriver);
try {
conn = DriverManager.getConnection(url, user, password);
QueryRunner qr = new QueryRunner();
List results = (List) qr.query(conn, "select id,name from guestbook", new MapListHandler());
for (int i = 0; i < results.size(); i++) {
Map map = (Map) results.get(i);
System.out.println("id:" + map.get("id") + ",name:" + map.get("name"));
}
} catch (SQLException e) {
e.printStackTrace();
} finally {
DbUtils.closeQuietly(conn);
}
}
}
在Hibernate中这个类叫做POJO类,
当然他可以使用映射文件“Guestbook.hbm.xml”或者annotation
Guestbook.java
代码:
package webbook.chapter5;
public class Guestbook {
private Integer id;
private String name;
public Integer getId() {
return id;
}
public void setId(Integer id) {
this.id = id;
}
public String getName() {
return name;
}
public void setName(String name) {
this.name = name;
}
}
BeanListExample.java
代码:
package webbook.chapter5;
import org.apache.commons.dbutils.DbUtils;
import org.apache.commons.dbutils.QueryRunner;
import org.apache.commons.dbutils.handlers.BeanListHandler;
import java.sql.Connection;
import java.sql.DriverManager;
import java.sql.SQLException;
import java.util.List;
public class BeanListExample {
public static void main(String[] args) {
Connection conn = null;
String url = "jdbc:oracle:thin:@10.5.116.112:1521:ora9";
String jdbcDriver = "oracle.jdbc.driver.OracleDriver";
String user = "scott";
String password = "tiger";
String sql="select id,name from guestbook";
DbUtils.loadDriver(jdbcDriver);
try {
conn = DriverManager.getConnection(url, user, password);
QueryRunner qr = new QueryRunner();
List results = (List) qr.query(conn, sql,new BeanListHandler(Guestbook.class));
for (int i = 0; i < results.size(); i++) {
Guestbook gb = (Guestbook) results.get(i);
System.out.println("id:" + gb.getId() + ",name:" + gb.getName());
}
} catch (SQLException e) {
e.printStackTrace();
} finally {
DbUtils.closeQuietly(conn);
}
}
}