东软培训-002
数据库操作
实体bean
package org.mo.model;
public class UserModel {
private Integer id;
private String name;
private Integer age;
private String sex;
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;
}
public Integer getAge() {
return age;
}
public void setAge(Integer age) {
this.age = age;
}
public String getSex() {
return sex;
}
public void setSex(String sex) {
this.sex = sex;
}
}
//查询类
package org.mo.model;
public class UserQueryModel extends UserModel {
private Integer age2;
public Integer getAge2() {
return age2;
}
public void setAge2(Integer age2) {
this.age2 = age2;
}
}
//连接数据库操作类
package org.mo.uitl;
import java.sql.SQLException;
import javax.sql.DataSource;
import org.apache.commons.dbcp.BasicDataSource;
public class ConnectionUtils {
private BasicDataSource basicDataSource = new BasicDataSource();
private ConnectionUtils() {
//兼容旧版本
basicDataSource.setDriverClassName("org.gjt.mm.mysql.Driver");
basicDataSource
.setUrl("jdbc:mysql://localhost:3306/test?useUnicode=true&characterEncoding=gb2312");
basicDataSource.setUsername("root");
basicDataSource.setPassword("root");
}
public void close() throws SQLException {
basicDataSource.close();
}
/**
* 内部类
*
* @author Administrator
*
*/
private static class SingletonHolder {
//饿汉式
private static ConnectionUtils intance = new ConnectionUtils();
}
public static ConnectionUtils getIntance() {
return SingletonHolder.intance;
}
public DataSource getDataSource() {
return basicDataSource;
}
}
//DAO
package org.mo.DAO;
import java.sql.Connection;
import java.sql.PreparedStatement;
import java.sql.ResultSet;
import java.sql.SQLException;
import java.util.ArrayList;
import java.util.List;
import org.mo.model.UserModel;
import org.mo.model.UserQueryModel;
import org.mo.uitl.ConnectionUtils;
public class UserJDBCDAO {
public void create(UserModel userModel) {
Connection connection = null;
try {
connection = ConnectionUtils.getIntance().getDataSource().getConnection();
final String SQL="INSERT INTO tbl_user(id, name, age, sex) VALUES(?,?,?,?)";
PreparedStatement ps = connection.prepareStatement(SQL);
ps.setInt(1, userModel.getId());
ps.setString(2, userModel.getName());
ps.setInt(3, userModel.getAge());
ps.setString(4, userModel.getSex());
ps.execute();
ps.close();
} catch (Exception e) {
}finally{
try {
connection.close();
} catch (SQLException e) {
e.printStackTrace();
}
}
}
public void update(UserModel userModel){
Connection connection = null;
try {
connection = ConnectionUtils.getIntance().getDataSource().getConnection();
final String SQL="UPDATE tbl_user SET name = ?, age = ?, sex = ? WHERE id = ?";
PreparedStatement ps = connection.prepareStatement(SQL);
ps.setString(1, userModel.getName());
ps.setInt(2, userModel.getAge());
ps.setString(3, userModel.getSex());
ps.setInt(4, userModel.getId());
ps.execute();
ps.close();
} catch (Exception e) {
}finally{
try {
connection.close();
} catch (SQLException e) {
e.printStackTrace();
}
}
}
public void delete(Integer id){
Connection connection = null;
try {
connection = ConnectionUtils.getIntance().getDataSource().getConnection();
final String SQL="DELETE tbl_user WHERE id = ?";
PreparedStatement ps = connection.prepareStatement(SQL);
ps.setInt(1, id);
ps.execute();
ps.close();
} catch (Exception e) {
}finally{
try {
connection.close();
} catch (SQLException e) {
e.printStackTrace();
}
}
}
public UserModel getSingle(Integer id){
Connection connection = null;
UserModel userModel = null;
try {
connection = ConnectionUtils.getIntance().getDataSource().getConnection();
final String SQL="select id, name, age, sex FROM tbl_user WHERE id = ?";
PreparedStatement ps = connection.prepareStatement(SQL);
ps.setInt(1, id);
ResultSet executeQuery = ps.executeQuery();
if(executeQuery.next()){
userModel = rsModel(executeQuery);
}
executeQuery.close();
ps.close();
} catch (Exception e) {
}finally{
try {
connection.close();
} catch (SQLException e) {
e.printStackTrace();
}
}
return userModel;
}
public List<UserModel> getAll(){
Connection connection = null;
List<UserModel> userModels = new ArrayList<UserModel>();
try {
connection = ConnectionUtils.getIntance().getDataSource().getConnection();
final String SQL="SELECT id, name, age, sex FROM tbl_user";
PreparedStatement ps = connection.prepareStatement(SQL);
ResultSet executeQuery = ps.executeQuery();
if(executeQuery.next()){
UserModel userModel = rsModel(executeQuery);
userModels.add(userModel);
}
executeQuery.close();
ps.close();
} catch (Exception e) {
}finally{
try {
connection.close();
} catch (SQLException e) {
e.printStackTrace();
}
}
return userModels;
}
private UserModel rsModel(ResultSet executeQuery) throws SQLException {
UserModel userModel = new UserModel();
int int1 = executeQuery.getInt("id");
String string = executeQuery.getString("name");
int int2 = executeQuery.getInt("age");
String string2 = executeQuery.getString("sex");
userModel.setId(int1);
userModel.setName(string);
userModel.setAge(int2);
userModel.setSex(string2);
return userModel;
}
private String genWhere(UserQueryModel userQuseryModel) {
StringBuffer stringBuffer = new StringBuffer();
if(userQuseryModel.getId() > 0){
stringBuffer.append(" and id = ? ");
}
if (userQuseryModel.getName().trim().length() > 0
|| userQuseryModel.getName() != null) {
stringBuffer.append(" and name like ? ");
}
if (userQuseryModel.getSex().trim().length() > 0
|| userQuseryModel.getSex() != null) {
stringBuffer.append(" and sex = ? ");
}
if(userQuseryModel.getAge() > 0 ){
stringBuffer.append(" and age >= ? ");
}
if(userQuseryModel.getAge2() > 0 ){
stringBuffer.append(" and age <= ? ");
}
return stringBuffer.toString();
}
private void preparePs(UserQueryModel uqm, PreparedStatement ps) throws Exception {
int count = 1;
if (uqm.getId() > 0) {
ps.setInt(count++, uqm.getId());
}
if (uqm.getName() != null && uqm.getName().trim().length() > 0) {
ps.setString(count++, uqm.getName());
}
if (uqm.getSex() != null && uqm.getSex().trim().length() > 0) {
ps.setString(count++, uqm.getSex());
}
if (uqm.getAge() > 0) {
ps.setInt(count++, uqm.getAge());
}
if (uqm.getAge2() > 0) {
ps.setInt(count++, uqm.getAge2());
}
}
public List<UserModel> getByCondition(UserQueryModel model){
Connection connection = null;
List<UserModel> userModels = new ArrayList<UserModel>();
try {
connection = ConnectionUtils.getIntance().getDataSource().getConnection();
final String SQL="SELECT id, name, age, sex FROM tbl_user WHERE 1=1 "
+ genWhere(model) + " ORDER BY id ";
PreparedStatement ps = connection.prepareStatement(SQL);
preparePs(model, ps);
ResultSet executeQuery = ps.executeQuery();
if(executeQuery.next()){
UserModel userModel = rsModel(executeQuery);
userModels.add(userModel);
}
executeQuery.close();
ps.close();
} catch (Exception e) {
}finally{
try {
connection.close();
} catch (SQLException e) {
e.printStackTrace();
}
}
return userModels;
}
}
//jar包
mysql-connector-java-5.1.8-bin.jar
commons-pool.jar
commons-dbcp.jar