java mySQLDBHelper类

ConnectionManager.java

import java.sql.*;
public class ConnectionManager {
public final static String DRIVER = "com.mysql.jdbc.Driver"; // 数据库驱动
public final static String URL = "jdbc:mysql://192.168.xx.xxx:3306/xxx"; // URL
public final static String DBUSER = "xxxx"; // 数据库用户名
public final static String DBPASS = "xxxx"; // 数据库密码

/*
* 得到数据库连接
*
* @throws Exception
*
* @return 数据库连接对象
*/
public static Connection getConnection() {
Connection dbConnection = null;
try {
// 把JDBC驱动类装载入Java虚拟机中
Class.forName(DRIVER);
// 加载驱动，并与数据库建立连接
dbConnection = DriverManager.getConnection(URL,DBUSER, DBPASS);
} catch (Exception e) {
e.printStackTrace();
}
return dbConnection;
}

public static void closeConnection(Connection dbConnection) {
try {
if (dbConnection != null && !dbConnection.isClosed()) {
dbConnection.close();
}
} catch (SQLException sqlEx) {
sqlEx.printStackTrace();
}
}
public static void closeResultSet(ResultSet res){
try{
if(res != null){
res.close();
res = null;
}
}catch(SQLException e){
e.printStackTrace();
}
}
public static void closeStatement(PreparedStatement pStatement){
try{
if(pStatement != null){
pStatement.close();
pStatement = null;
}
}catch(SQLException e){
e.printStackTrace();
}
}
}

DBHelperMySQL.java

import java.lang.reflect.Field;
import java.lang.reflect.Method;
import java.sql.Connection;
import java.sql.PreparedStatement;
import java.sql.ResultSet;
import java.sql.SQLException;
import java.sql.Timestamp;
import java.util.ArrayList;
import java.util.Date;
import java.util.List;

public final class DBHelperMySQL {
/**
* 用于执行语句（eg：insert语句，update语句，delete语句）
*
* @param SQL语句
* @param 参数集合
* @return 影响的行数
*/
public static int ExecuteNonQuery(String cmdtext, Object[] params)
throws Exception {
PreparedStatement pstmt = null;
Connection conn = null;
try {
conn = ConnectionManager.getConnection();
pstmt = conn.prepareStatement(cmdtext);
PrepareCommand(pstmt, params);
return pstmt.executeUpdate();
} catch (SQLException sqlE) {
throw new Exception("ExecuteNonQuery方法出错:" + sqlE.getMessage());
} finally {
ConnectionManager.closeStatement(pstmt);
ConnectionManager.closeConnection(conn);
}
}

/**
* 用于查找单条数据（Select * from where id =0）
*
* @param 查询语句
* @param 查询参数
* @param 返回类型
* @return 查询实体对象
* @throws 异常
*/
public static Object getModel(String cmdtext, Object[] params,
Class<?> classObj) throws Exception {
PreparedStatement pstmt = null;
Connection conn = null;
ResultSet rs = null;
try {
conn = ConnectionManager.getConnection();
pstmt = conn.prepareStatement(cmdtext);
PrepareCommand(pstmt, params);
rs = pstmt.executeQuery();
Object obj = classObj.newInstance();
Field[] fields = classObj.getDeclaredFields();
if (rs.next()) {
for (Field item : fields) {
if (!item.getName().equals("serialVersionUID")) {
System.out.println(rs.getString(item.getName()));
item.setAccessible(true);
Class<?> type = item.getType();
if (type.isPrimitive() == true) {
item.set(
obj,
convert(item.getType().toString(),
rs.getString(item.getName())));
} else {
if (item.getType().getName()
.equals("java.lang.String")) {
item.set(obj, rs.getString(item.getName()));
} else if (item.getType().getName()
.equals("java.util.Date")) {
Date date = Timestamp.valueOf(rs.getString(item
.getName()));
item.set(obj, date);
} else {
Method m = type.getMethod("valueOf",
String.class);
item.set(
obj,
m.invoke(null,
rs.getString(item.getName())));
}
}
item.setAccessible(false);
}
}
return obj;
}
return null;
} catch (SQLException sqlE) {
System.out.println(sqlE.getMessage());
throw new Exception("ExecuteNonQuery方法出错:" + sqlE.getMessage());
} finally {
ConnectionManager.closeResultSet(rs);
ConnectionManager.closeStatement(pstmt);
ConnectionManager.closeConnection(conn);
}
}

/**
* 用于获取结果集语句（eg：selete * from table）
*
* @param 查询语句
* @param 查询参数
* @param 返回类型
* @return 查询实体对象
* @throws 异常
*/
public static List<?> ExecuteReader(String cmdtext, Object[] params,
Class<?> classObj) throws Exception {
PreparedStatement pstmt = null;
Connection conn = null;
ResultSet rs = null;
try {
conn = ConnectionManager.getConnection();
pstmt = conn.prepareStatement(cmdtext);
PrepareCommand(pstmt, params);
rs = pstmt.executeQuery();
@SuppressWarnings({ "rawtypes", "unchecked" })
List<Object> list = new ArrayList();
Field[] fields = classObj.getDeclaredFields();
while (rs.next()) {
Object obj = classObj.newInstance();
for (Field item : fields) {
if (!item.getName().equals("serialVersionUID")) {
item.setAccessible(true);
Class<?> type = item.getType();
try {
if (type.isPrimitive() == true) {
item.set(
obj,
convert(item.getType().toString(),
rs.getString(item.getName())));
} else {
if (item.getType().getName()
.equals("java.lang.String")) {
item.set(obj, rs.getString(item.getName()));
} else if (item.getType().getName()
.equals("java.util.Date")) {
Date date = Timestamp.valueOf(rs
.getString(item.getName()));
item.set(obj, date);
} else {
Method m = type.getMethod("valueOf",
String.class);
item.set(obj, m.invoke(null,
rs.getString(item.getName())));
}
}
} catch (Exception e) {
continue;
}
item.setAccessible(false);
}
}
System.out.println(obj.toString());
list.add(obj);
}
return list;
} catch (SQLException sqlE) {
System.out.println(sqlE.getMessage());
throw new Exception("ExecuteNonQuery方法出错:" + sqlE.getMessage());
} finally {
ConnectionManager.closeResultSet(rs);
ConnectionManager.closeStatement(pstmt);
ConnectionManager.closeConnection(conn);
}
}

/**
* 用于获取单字段值语句（用名字指定字段）
*
* @param cmdtext
*            SQL语句
* @param name
*            列名
* @param params
*            OracleParameter[]
* @return Object
* @throws Exception
*/
public static Object ExecuteScalar(String cmdtext, String name,
Object[] params) throws Exception {
PreparedStatement pstmt = null;
Connection conn = null;
ResultSet rs = null;

try {
conn = ConnectionManager.getConnection();

pstmt = conn.prepareStatement(cmdtext);
PrepareCommand(pstmt, params);

rs = pstmt.executeQuery();
if (rs.next()) {
return rs.getObject(name);
} else {
return null;
}
} catch (SQLException sqlE) {
throw new Exception("ExecuteSqlObject方法出错:" + sqlE.getMessage());
} finally {
ConnectionManager.closeResultSet(rs);
ConnectionManager.closeStatement(pstmt);
ConnectionManager.closeConnection(conn);
}
}

/**
* 用于获取单字段值语句（用序号指定字段）
*
* @param cmdtext
*            SQL语句
* @param index
*            列名索引
* @param params
*            OracleParameter[]
* @return Object
* @throws Exception
*/
public static Object ExecuteScalar(String cmdtext, int index,
Object[] params) throws Exception {
PreparedStatement pstmt = null;
Connection conn = null;
ResultSet rs = null;
try {
conn = ConnectionManager.getConnection();
pstmt = conn.prepareStatement(cmdtext);
PrepareCommand(pstmt, params);
rs = pstmt.executeQuery();
if (rs.next()) {
return rs.getObject(index);
} else {
return null;
}
} catch (SQLException sqlE) {
throw new Exception("ExecuteSqlObject方法出错:" + sqlE.getMessage());
} finally {
ConnectionManager.closeResultSet(rs);
ConnectionManager.closeStatement(pstmt);
ConnectionManager.closeConnection(conn);
}
}

/**
* 准备SQL参数
*
* @param pstm
* @param params
*/
public static vo
4000
id PrepareCommand(PreparedStatement pstm, Object[] params) {
if (params == null || params.length == 0) {
System.out.println(pstm.toString());
return;
}
try {
for (int i = 0; i < params.length; i++) {
int parameterIndex = i + 1;
pstm.setString(parameterIndex, params[i].toString());
}
System.out.println(pstm.toString());
} catch (Exception e) {
}
}

/**
* 转换基础类型数据
*
* @param 基础类型
* @param 要设置的值
* @return 值对象
*/
private static Object convert(String type, String value) {
if (type.equals("int"))
return new Integer(value);
if (type.equals("double"))
return new Double(value);
if (type.equals("float"))
return new Float(value);
return null;
}
}

MemberDaoImpl.java

import java.util.List;

import org.springframework.stereotype.Repository;

import com.jiayuan.ktv.common.DBHelperMySQL;
import com.jiayuan.ktv.dao.MemberDao;
import com.jiayuan.ktv.entity.Member;

@Repository("memberDao")
public class MemberDaoImpl implements MemberDao {

/**
* 保存
*
* @param member
*/
@Override
public int save(Member member) {
try {
String sql = "INSERT INTO member(WXUserName,MemberType,Phone,Card,AddDate)"
+ "VALUES(?,?,?,?,?)";
String[] params = { String.valueOf(member.getWxusername()),String.valueOf(member.getMemberType()),String.valueOf(member.getPhone()),String.valueOf(member.getCard()),String.valueOf(member.getAdddate())};
return DBHelperMySQL.ExecuteNonQuery(sql, params);
} catch (Exception e) {
e.printStackTrace();
return 0;
}
}
/**
* 修改
*
* @param member
*/
@Override
public int update(Member member) {
try {
String sql = "UPDATE member SET WXUserName=?,MemberType=?,Phone=?,Card=?,AddDate=? where Id=?";
String[] params = { String.valueOf(member.getWxusername()),String.valueOf(member.getMemberType()),String.valueOf(member.getPhone()),String.valueOf(member.getCard()),String.valueOf(member.getAdddate()),String.valueOf(member.getId())};
return DBHelperMySQL.ExecuteNonQuery(sql, params);
} catch (Exception e) {
e.printStackTrace();
return 0;
}
}
/**
* 根据主键删除一条数据
*
* @param id
*/
@Override
public int delete(int id) {
try {
String sql = "DELETE FROM member WHERE Id=?";
String[] params = { String.valueOf(id) };
return DBHelperMySQL.ExecuteNonQuery(sql, params);
} catch (Exception e) {
e.printStackTrace();
return 0;
}
}
/**
* 根据主键集合删除一批数据
* @param ids
*/
@Override
public int deleteList(String ids) {
try {
String sql = "Delete From member WHERE Id in (" + ids + ")";
String[] params = { ids };
return DBHelperMySQL.ExecuteNonQuery(sql, params);
} catch (Exception e) {
e.printStackTrace();
return 0;
}
}
/**
* 通过主键获得Model
* @param id
* @return Model
*/
@Override
public Member getModel(int id) {
try {
String sql = "SELECT * FROM member WHERE Id=?";
String[] params = { String.valueOf(id) };
return (Member) DBHelperMySQL.getModel(sql, params,Member.class);
} catch (Exception e) {
e.printStackTrace();
return null;
}
}
/**
* 通过Sql语句获得Model
* @param sql
* @return Model
*/
@Override
public Member getModel(String sql) {
try {
sql = "SELECT * FROM member WHERE " + sql;
return (Member) DBHelperMySQL.getModel(sql, null,Member.class);
} catch (Exception e) {
return null;
}
}
/**
* 通过Sql语句获得数据列表
* @param sql
* @return
*/
@SuppressWarnings("unchecked")
@Override
public List<Member> getList(String sql) {
try {
if (sql.trim() != "")
sql = " WHERE " + sql;
sql = "SELECT * FROM member " + sql;
return (List<Member>) DBHelperMySQL.ExecuteReader(sql,null,Member.class);
} catch (Exception e) {
return null;
}
}
/**
* 分页查询
* @param 条件语句
* @param 起始位置
* @param 查询条数
* @return List
*/
@SuppressWarnings("unchecked")
@Override
public List<Member> getList(String sql, int startIndex, int rows) {
try {
if (sql.trim() != "")
sql = " WHERE " + sql;
sql = "SELECT * FROM member "+sql+" LIMIT " + startIndex + ","+ rows;
return (List<Member>) DBHelperMySQL.ExecuteReader(sql,null,Member.class);
} catch (Exception e) {
return null;
}
}

/**
* 获得总数
*/
@Override
public int getCount(String sql) {
try {
if (sql.trim() != "")
sql = " WHERE " + sql;
sql = "select count(Id) as Id from member "
+ sql;
Object o = DBHelperMySQL.ExecuteScalar(sql, "Id", null);
if (o != null) {
return Integer.parseInt(o.toString());
} else
return 0;
} catch (Exception e) {
return 0;
}
}
}