Apache DBUtils常用方法總結

首先我們的明白Apache DBUtils是幹什麼用的：它是dao層的一個幫助類，簡化了dao層jdbc的開發，下面直接開始講述實現步驟：

1.下載commons-dbutils-1.7.jar
其中包含了三個基本類：
DbUtils輔助,QueryRunner：增刪改查. ResultSetHandler查詢返回集合
還需要引入一種數據源的jar，和jdbc的jar。
下面是各自的常用方法
1.DbUtils常用方法：

2.QueryRunner類常用方法：

3.ResultSetHandler：

測試：

數據庫的表：

Student類：

package Clss.apacheddbutil;

public class Student {
private int stuno;
private String stuname;
private int stuage;
private String gname;

public Student(int stuno, String stuname, int stuage, String gname) {
        this.stuno = stuno;
        this.stuname = stuname;
        this.stuage = stuage;
        this.gname = gname;
    }
    public Student() {

    }
    public int getStuno() {
        return stuno;
    }

    public void setStuno(int stuno) {
        this.stuno = stuno;
    }

    public String getStuname() {
        return stuname;
    }

    public void setStuname(String stuname) {
        this.stuname = stuname;
    }

    public int getStuage() {
        return stuage;
    }

    public void setStuage(int stuage) {
        this.stuage = stuage;
    }

    public String getGname() {
        return gname;
    }

    public void setGname(String gname) {
        this.gname = gname;
    }
}

查詢：

package Clss.apacheddbutil;

import org.apache.commons.dbutils.QueryRunner;
import org.apache.commons.dbutils.handlers.*;
import util.DataSourceUtil;

import java.math.BigDecimal;
import java.sql.SQLException;
import java.sql.SQLOutput;
import java.util.List;
import java.util.Map;

public class query {
    //查詢,自動提交事務
    //返回單行Object
    public static void testArrayHandler() throws SQLException {
        QueryRunner runner = new QueryRunner(DataSourceUtil.getDataSourceWithC3P0ByXml());
        Object[] student = runner.query("select *from student where stuno >? and stuname like ?",new ArrayHandler(),new Object[]{10,"%z%"});//ArrayHandaler只取一行
        System.out.println(student.length);
        System.out.println(student[0]+","+student[1]+","+student[2]+","+student[3]);
    }//順序默認是oracle 表的順序
    //返回多行Object
    public static void testArrayListHandler() throws SQLException {
        QueryRunner runner = new QueryRunner(DataSourceUtil.getDataSourceWithC3P0ByXml());
        List<Object[]> students = runner.query("select *from student where stuno >?",new ArrayListHandler(),5);//ArrayHandaler只取一行
        for(Object[] student:students){
            System.out.println(student[0]+","+student[1]+","+student[2]+","+student[3]);
        }//順序默認是oracle表的順序

    }


    //Student
    //查詢單行數據（放入對象中）
    public static void testBeanHandler() throws SQLException {
        QueryRunner runner = new QueryRunner(DataSourceUtil.getDataSourceWithC3P0ByXml());
        Student student = runner.query("select *from student where stuno >?",new BeanHandler<Student>(Student.class),10);//ArrayHandaler只取一行
        System.out.println(student.getStuname()+","+student.getStuno()+","+student.getStuage()+","+student.getGname());
    }//注意創建的Student類裏面的參數必須和該表的屬性一模一樣  比如說必須是Student類裏面必須定義stuno ，不能寫成stu
    //輸出可以根據自己的喜好  調整輸出參數的位置


    //查詢多行數據
    public static void testBeanListHandler() throws SQLException {
        QueryRunner runner = new QueryRunner(DataSourceUtil.getDataSourceWithC3P0ByXml());
        List<Student> students = runner.query("select *from student where stuno >?",new BeanListHandler<Student>(Student.class),10);//ArrayHandaler只取一行
        for(Student student:students) {
            System.out.println(student.getStuname() + "," + student.getStuno() + "," + student.getStuage() + "," + student.getGname());
        }
    }

    //查詢多行數據（放入map中）
    public static void testBeanMapHandler() throws SQLException {
        QueryRunner runner = new QueryRunner(DataSourceUtil.getDataSourceWithC3P0ByXml());                        //注意Oracle默認數據類型是BigDecimal,不能用Integer
        Map<BigDecimal,Student> students = runner.query("select *from student where stuno >?",new BeanMapHandler<BigDecimal,Student>(Student.class,"stuno"),10);//ArrayHandaler只取一行
        Student stu = students.get(new BigDecimal(13));//坑！！！！！不能寫13 必須轉成BigDecimal類型
        System.out.println(stu.getStuname() + "," + stu.getStuno() + "," + stu.getStuage() + "," + stu.getGname());
    }


////////////////.......................................Map   ->返回的結果爲前面有屬性名
    //返回第一行數據
public static void testMapHandler() throws SQLException {
    QueryRunner runner = new QueryRunner(DataSourceUtil.getDataSourceWithC3P0ByXml());
    Map<String,Object> student = runner.query("select *from student where stuno >?",new MapHandler(),656);
    System.out.println(student);
}
    //返回第多行數據
    public static void testMapListHandler() throws SQLException {
        QueryRunner runner = new QueryRunner(DataSourceUtil.getDataSourceWithC3P0ByXml());
        List<Map<String,Object>> students = runner.query("select *from student where stuno >?",new MapListHandler(),10);
        for(Map<String,Object> student:students)
        System.out.println(student);
    }

//多行加字段   給{}一個key值
public static void testKeyedHandler() throws SQLException {
    QueryRunner runner = new QueryRunner(DataSourceUtil.getDataSourceWithC3P0ByXml());
    Map<String,Map<String,Object>> students = runner.query("select *from student where stuno >?",new KeyedHandler<String>("stuname"),10);
    System.out.println(students);
}

///////////////////................................................把結果集中的某一列  保存到List中
public static void testColumnListHandler() throws SQLException {
    QueryRunner runner = new QueryRunner(DataSourceUtil.getDataSourceWithC3P0ByXml());
    List<String> students = runner.query("select *from student where stuno >?",new ColumnListHandler<String>("stuname"),10);
    System.out.println(students);
}
//ScalarHandler ：單值結果
public static void testScalarHandler() throws SQLException {
    QueryRunner runner = new QueryRunner(DataSourceUtil.getDataSourceWithC3P0ByXml());
    BigDecimal result = runner.query("select count(1) from student where stuno >?",new ScalarHandler<BigDecimal>(),10);
    System.out.println(result);//sql: select stuno from student where stu0= ?;  param:13
}
public static void main(String[] args) throws SQLException {
//        testArrayHandler();
           testArrayListHandler();
        //testBeanHandler();
//        testBeanListHandler();
        //testBeanMapHandler();
//        testMapHandler();
//        testMapListHandler();
//        testKeyedHandler();
//        testColumnListHandler();
        //testScalarHandler();
    }
}

增刪改：

package Clss.apacheddbutil;

import org.apache.commons.dbutils.QueryRunner;
import util.DataSourceUtil;

import java.sql.SQLException;

public class UpdateDemo {
    //自動提交
    //增加
    public static void add() throws SQLException {
        QueryRunner runner = new QueryRunner(DataSourceUtil.getDataSourceWithC3P0ByXml());
        int count = runner.update("insert into student(stuno,stuname,stuage,gname) values(?,?,?,?)",new Object[]{50,"huhuilin",18,"sss"});
        System.out.println(count);//返回增刪改的 條數
    }

    //刪除
    public static void delete() throws SQLException {
        QueryRunner runner = new QueryRunner(DataSourceUtil.getDataSourceWithC3P0ByXml());
        int count = runner.update("delete from student where stuno = ?",999);
        System.out.println(count);//返回增刪改的 條數
    }

    //修改
    public static void update() throws SQLException {
        QueryRunner runner = new QueryRunner(DataSourceUtil.getDataSourceWithC3P0ByXml());
        int count = runner.update("update student set stuname=? where stuno=?",new Object[]{"wangyin",4});
        System.out.println(count);//返回增刪改的 條數
    }

  public static void main(String[] args) throws SQLException {
//        add();
//        delete();
          update();
    }
}

注意，有些ojdbc.jar包和本項目不兼容！