Java实例---简单的数据库操作
源码分析
DAOFactory.java
1 package cn.ftl.mysql ;
2 public class DAOFactory {
3 public static IEmpDAO getIEmpDAOInstance() throws Exception{
4 return new EmpDAOProxy() ;
5 }
6 }
View Code
DatabaseConnection.java
1 package cn.ftl.mysql ;
2 import java.sql.Connection ;
3 import java.sql.DriverManager ;
4 public class DatabaseConnection {
5 public static final String DBDRIVER= "com.mysql.jdbc.Driver";
6 public static final String DBURL= "jdbc:mysql://localhost:3306/RUNOOB";
7 public static final String DBUSER= "test";
8 public static final String DBPASSWORD= "Changeme_123";
9
10 private Connection conn ;
11 public DatabaseConnection() throws Exception {
12 Class.forName(DBDRIVER) ;
13 this.conn = DriverManager.getConnection(DBURL,DBUSER,DBPASSWORD) ;
14 }
15 public Connection getConnection(){
16 return this.conn ;
17 }
18 public void close() throws Exception {
19 if(this.conn != null){
20 try{
21 this.conn.close() ;
22 }catch(Exception e){
23 throw e ;
24 }
25 }
26 }
27 }
View Code
Emp.java
1 package cn.ftl.mysql ;
2 import java.util.Date ;
3 public class Emp {
4 private int empno ;
5 private String ename ;
6 private String job ;
7 private Date hiredate ;
8 private float sal ;
9 public void setEmpno(int empno){
10 this.empno = empno ;
11 }
12 public void setEname(String ename){
13 this.ename = ename ;
14 }
15 public void setJob(String job){
16 this.job = job ;
17 }
18 public void setHiredate(Date hiredate){
19 this.hiredate = hiredate ;
20 }
21 public void setSal(float sal){
22 this.sal = sal ;
23 }
24 public int getEmpno(){
25 return this.empno ;
26 }
27 public String getEname(){
28 return this.ename ;
29 }
30 public String getJob(){
31 return this.job ;
32 }
33 public Date getHiredate(){
34 return this.hiredate ;
35 }
36 public float getSal(){
37 return this.sal ;
38 }
39 }
View Code
EmpDAOImpl.java
1 package cn.ftl.mysql;
2
3 import java.util.* ;
4 import java.sql.* ;
5
6 public class EmpDAOImpl implements IEmpDAO {
7 private Connection conn = null ;
8 private PreparedStatement pstmt = null ;
9 public EmpDAOImpl(Connection conn){
10 this.conn = conn ;
11 }
12 public boolean doCreate(Emp emp) throws Exception{
13 boolean flag = false ;
14 String sql = "INSERT INTO emp(empno,ename,job,hiredate,sal) VALUES (?,?,?,?,?)" ;
15 this.pstmt = this.conn.prepareStatement(sql) ;
16 this.pstmt.setInt(1,emp.getEmpno()) ;
17 this.pstmt.setString(2,emp.getEname()) ;
18 this.pstmt.setString(3,emp.getJob()) ;
19 this.pstmt.setDate(4,new java.sql.Date(emp.getHiredate().getTime())) ;
20 this.pstmt.setFloat(5,emp.getSal()) ;
21 if(this.pstmt.executeUpdate() > 0){
22 flag = true ;
23 }
24 this.pstmt.close() ;
25 return flag ;
26 }
27 public List<Emp> findAll(String keyWord) throws Exception{
28 List<Emp> all = new ArrayList<Emp>() ;
29 String sql = "SELECT empno,ename,job,hiredate,sal FROM emp WHERE ename LIKE ? OR job LIKE ?" ;
30 this.pstmt = this.conn.prepareStatement(sql) ;
31 this.pstmt.setString(1,"%"+keyWord+"%") ;
32 this.pstmt.setString(2,"%"+keyWord+"%") ;
33 ResultSet rs = this.pstmt.executeQuery() ;
34 Emp emp = null ;
35 while(rs.next()){
36 emp = new Emp() ;
37 emp.setEmpno(rs.getInt(1)) ;
38 emp.setEname(rs.getString(2)) ;
39 emp.setJob(rs.getString(3)) ;
40 emp.setHiredate(rs.getDate(4)) ;
41 emp.setSal(rs.getFloat(5)) ;
42 all.add(emp) ;
43 }
44 this.pstmt.close() ;
45 return all ;
46 }
47 public Emp findById(int empno) throws Exception{
48 Emp emp = null ;
49 String sql = "SELECT empno,ename,job,hiredate,sal FROM emp WHERE empno=?" ;
50 this.pstmt = this.conn.prepareStatement(sql) ;
51 this.pstmt.setInt(1,empno) ;
52 ResultSet rs = this.pstmt.executeQuery() ;
53 if(rs.next()){
54 emp = new Emp() ;
55 emp.setEmpno(rs.getInt(1)) ;
56 emp.setEname(rs.getString(2)) ;
57 emp.setJob(rs.getString(3)) ;
58 emp.setHiredate(rs.getDate(4)) ;
59 emp.setSal(rs.getFloat(5)) ;
60 }
61 this.pstmt.close() ;
62 return emp ;
63 }
64 }
View Code
EmpDAOProxy.java
1 package cn.ftl.mysql;
2
3 import java.util.* ;
4 import java.sql.* ;
5
6 public class EmpDAOProxy implements IEmpDAO {
7 private DatabaseConnection dbc = null ;
8 private IEmpDAO dao = null ;
9 public EmpDAOProxy() throws Exception {
10 this.dbc = new DatabaseConnection() ;
11 this.dao = new EmpDAOImpl(this.dbc.getConnection()) ;
12 }
13 public boolean doCreate(Emp emp) throws Exception{
14 boolean flag = false ;
15 try{
16 if(this.dao.findById(emp.getEmpno()) == null){
17 flag = this.dao.doCreate(emp) ;
18 }
19 }catch(Exception e){
20 throw e ;
21 }finally{
22 this.dbc.close() ;
23 }
24 return flag ;
25 }
26 public List<Emp> findAll(String keyWord) throws Exception{
27 List<Emp> all = null ;
28 try{
29 all = this.dao.findAll(keyWord) ;
30 }catch(Exception e){
31 throw e ;
32 }finally{
33 this.dbc.close() ;
34 }
35 return all ;
36 }
37 public Emp findById(int empno) throws Exception{
38 Emp emp = null ;
39 try{
40 emp = this.dao.findById(empno) ;
41 }catch(Exception e){
42 throw e ;
43 }finally{
44 this.dbc.close() ;
45 }
46 return emp ;
47 }
48 }
View Code
IEmpDAO.java
1 package cn.ftl.mysql;
2 import java.util.* ;
3 public interface IEmpDAO {
4 public boolean doCreate(Emp emp) throws Exception ;
5 public List<Emp> findAll(String keyWord) throws Exception ;
6 public Emp findById(int empno) throws Exception ;
7 }
View Code
TestDAOInsert.java
1 package cn.ftl.mysql;
2 public class TestDAOInsert{
3 public static void main(String args[]) throws Exception{
4 Emp emp = null ;
5 for(int x=0;x<5;x++){
6 emp = new Emp() ;
7 emp.setEmpno(101 + x) ;
8 emp.setEname("FTL - " + x) ;
9 emp.setJob("JC - " + x) ;
10 emp.setHiredate(new java.util.Date()) ;
11 emp.setSal(5 * x) ;
12 DAOFactory.getIEmpDAOInstance().doCreate(emp) ;
13 }
14 }
15 }
View Code
TestDAOSelect.java
1 package cn.ftl.mysql;
2 import java.util.* ;
3 public class TestDAOSelect{
4 public static void main(String args[]) throws Exception{
5 List<Emp> all = DAOFactory.getIEmpDAOInstance().findAll("") ;
6 Iterator<Emp> iter = all.iterator() ;
7 while(iter.hasNext()){
8 Emp emp = iter.next() ;
9 System.out.println(emp.getEmpno() + "、" + emp.getEname() + " --> " + emp.getJob()) ;
10 }
11 }
12 }
View Code
源码下载
【更多参考】
Java学习---连接数据库操作
数据库建模工具 PD的使用
Linu下的Mysql学习详解_【all】
作者：小a玖拾柒
-------------------------------------------
个性签名: 所有的事情到最後都是好的，如果不好，那說明事情還沒有到最後～
本文版权归作者【小a玖拾柒】，欢迎转载，但未经作者同意必须保留此段声明，且在文章页面明显位置给出原文连接，否则保留追究法律责任的权利！
