Java完成Dbhelper支撐年夜數據增刪改。本站提示廣大學習愛好者:(Java完成Dbhelper支撐年夜數據增刪改)文章只能為提供參考,不一定能成為您想要的結果。以下是Java完成Dbhelper支撐年夜數據增刪改正文
在做項目標時刻,技巧選型很主要,在底層的辦法直接影響了我們對年夜數據拜訪和修正的速度,在Java中有許多優良的ORM框架,好比說:JPA,Hibernate 等等,正如我們所說的,框架有框架的利益,固然也存在一些可以改良的處所,這個時刻,就須要我們針關於分歧的營業分歧的需求,分歧的拜訪量,對底層的架構從新封裝,來支撐年夜數據增刪改。
代碼:
import java.io.*;
import java.sql.*;
import java.util.*;
import java.util.logging.Level;
import java.util.logging.Logger;
import javax.servlet.jsp.jstl.sql.*;
/**
* DbHelper
* @author qmx
*
*/
public class Dbhelper {
private String sql; //要傳入的sql語句
public void setSql(String sql) {
this.sql = sql;
}
private List sqlValues; //sql語句的參數
public void setSqlValues(List sqlValues) {
this.sqlValues = sqlValues;
}
private List<List> sqlValue; //sql語句的參數
public void setSqlValue(List<List> sqlValues) {
this.sqlValue = sqlValues;
}
private Connection con; //銜接對象
public void setCon(Connection con) {
this.con = con;
}
public Dbhelper(){
this.con=getConnection(); //給Connection的對象賦初值
}
/**
* 獲得數據庫銜接
* @return
*/
private Connection getConnection(){
String driver_class=null;
String driver_url=null;
String database_user=null;
String database_password=null;
try {
InputStream fis=this.getClass().getResourceAsStream("/db.properties"); //加載數據庫設置裝備擺設文件到內存中
Properties p=new Properties();
p.load(fis);
driver_class=p.getProperty("driver_class"); //獲得數據庫設置裝備擺設文件
driver_url=p.getProperty("driver_url");
database_user=p.getProperty("database_user");
database_password=p.getProperty("database_password");
Class.forName(driver_class);
con=DriverManager.getConnection(driver_url,database_user,database_password);
} catch (ClassNotFoundException e) {
// TODO Auto-generated catch block
e.printStackTrace();
} catch (SQLException e) {
// TODO Auto-generated catch block
e.printStackTrace();
} catch (FileNotFoundException e) {
// TODO Auto-generated catch block
e.printStackTrace();
} catch (IOException e) {
// TODO Auto-generated catch block
e.printStackTrace();
}
return con;
}
/**
* 封閉數據庫
* @param con
* @param pst
* @param rst
*/
private void closeAll(Connection con,PreparedStatement pst,ResultSet rst){
if(rst!=null){
try {
rst.close();
} catch (SQLException e) {
// TODO Auto-generated catch block
e.printStackTrace();
}
}
if(pst!=null){
try {
pst.close();
} catch (SQLException e) {
// TODO Auto-generated catch block
e.printStackTrace();
}
}
if(con!=null){
try {
con.close();
} catch (SQLException e) {
// TODO Auto-generated catch block
e.printStackTrace();
}
}
}
/**
* 封閉數據庫
* @param con
* @param pst
* @param rst
*/
private void closeAll(Connection con,Statement pst,ResultSet rst){
if(rst!=null){
try {
rst.close();
} catch (SQLException e) {
// TODO Auto-generated catch block
e.printStackTrace();
}
}
if(pst!=null){
try {
pst.close();
} catch (SQLException e) {
// TODO Auto-generated catch block
e.printStackTrace();
}
}
if(con!=null){
try {
con.close();
} catch (SQLException e) {
// TODO Auto-generated catch block
e.printStackTrace();
}
}
}
/**
* 查找
* @param sql
* @param sqlValues
* @return
*/
public Result executeQuery(){
Result result=null;
ResultSet rst=null;
PreparedStatement pst=null;
try {
pst=con.prepareStatement(sql);
if(sqlValues!=null&&sqlValues.size()>0){ //當sql語句中存在占位符時
setSqlValues(pst,sqlValues);
}
rst=pst.executeQuery();
result=ResultSupport.toResult(rst); //必定要在封閉數據庫之前完成轉換
} catch (SQLException e) {
// TODO Auto-generated catch block
e.printStackTrace();
}finally{
this.closeAll(con, pst, rst);
}
return result;
}
/**
* 增刪改
* @return
*/
public int executeUpdate(){
int result=-1;
PreparedStatement pst=null;
try {
pst=con.prepareStatement(sql);
if(sqlValues!=null&&sqlValues.size()>0){ //當sql語句中存在占位符時
setSqlValues(pst,sqlValues);
}
result=pst.executeUpdate();
} catch (SQLException e) {
// TODO Auto-generated catch block
e.printStackTrace();
}finally{
this.closeAll(con, pst, null);
}
return result;
}
/**
* 應用PreparedStatement加批量的辦法
* @return
*/
public int[] executeUpdateMore(){
int[] result=null;
try{
PreparedStatement prest =con.prepareStatement(sql,ResultSet.TYPE_SCROLL_SENSITIVE,ResultSet.CONCUR_READ_ONLY);
for(List sqlValueString : sqlValue){
for(int i=0;i<sqlValueString.size();i++){
try {
prest.setObject(i+1,sqlValueString.get(i));
} catch (SQLException e) {
// TODO Auto-generated catch block
e.printStackTrace();
}
}
prest.addBatch();
}
prest.executeBatch();
/* con.commit();*/
this.closeAll(con, prest, null);
} catch (SQLException ex){
Logger.getLogger(Dbhelper.class.getName()).log(Level.SEVERE, null,ex);
}
return result;
}
/**
* 應用PreparedStatement加批量的辦法,strvalue:
* "INSERT INTOadlogs(ip,website,yyyymmdd,hour,object_id) VALUES('192.168.1.3','localhost','20081009',8,'23123')"
* @return
* @throws SQLException
*/
public int[] executeUpdateMoreNotAuto() throws SQLException{
int[] result =null;
con.setAutoCommit(false);
Statement stmt =con.createStatement(ResultSet.TYPE_SCROLL_SENSITIVE,
ResultSet.CONCUR_READ_ONLY);
String[] SqlString= null;
for(String strvalue : SqlString){
stmt.execute(strvalue);
}
con.commit();
return result;
}
/**
* 應用PreparedStatement加批量的辦法,strvalue:
* "INSERT INTOadlogs(ip,website,yyyymmdd,hour,object_id) VALUES('192.168.1.3','localhost','20081009',8,'23123')"
* @return
* @throws SQLException
*/
public int[] executeMoreNotAuto() throws SQLException{
//保留以後主動提交形式
Boolean booleanautoCommit=false;
String[] SqlString= null;
int[] result= null;
try
{
booleanautoCommit=con.getAutoCommit();
//封閉主動提交
con.setAutoCommit(false);
Statement stmt =con.createStatement(ResultSet.TYPE_SCROLL_SENSITIVE,
ResultSet.CONCUR_READ_ONLY);
//應用Statement同時搜集多條sql語句
/*stmt.addBatch(insert_sql1);
stmt.addBatch(insert_sql2);
stmt.addBatch(update_sql3);*/
for(String strvalue : SqlString){
stmt.addBatch(strvalue);
}
//同時提交一切的sql語句
stmt.executeBatch();
//提交修正
con.commit();
con.setAutoCommit(booleanautoCommit);
this.closeAll(con, stmt, null);
}
catch(Exception e)
{
e.printStackTrace();
con.rollback(); //設定setAutoCommit(false)沒有在catch中停止Connection的rollBack操作,操作的表就會被鎖住,形成數據庫逝世鎖
}
return result;
}
/**
* 給sql語句中的占位符賦值
* @param pst
* @param sqlValues
*/
private void setSqlValues(PreparedStatement pst,List sqlValues){
for(int i=0;i<sqlValues.size();i++){
try {
pst.setObject(i+1,sqlValues.get(i));
} catch (SQLException e) {
// TODO Auto-generated catch block
e.printStackTrace();
}
}
}
}
我們的在db.properties中寫入拜訪數據庫的信息:
driver_class=com.mysql.jdbc.Driver driver_url=jdbc:mysql://192.168.22.246:3306/importexceltest database_user=basic database_password=basic
測試:
import java.util.*;
public class ImportExcelTest {
public static void main(String[] args){
/*Dbhelper db = new Dbhelper();
String sql = "insert into tb_coursetype(id,courseTypeName) values('2012003','qmx3')";
db.setSql(sql);
db.executeUpdate();*/
/*Dbhelper db1 = new Dbhelper();
String sql1 = "insert into tb_coursetype(id,courseTypeName) values(?,?)";
List sqlValues = new ArrayList();
sqlValues.add("2012004");
sqlValues.add("qmx4");
db1.setSqlValues(sqlValues);
db1.setSql(sql1);
db1.executeUpdate();*/
Dbhelper db = new Dbhelper();
String sql = "insert into tb_coursetype(id,courseTypeName) values(?,?)";
List<List> sqlValues = new ArrayList();
List sqlValueString =new ArrayList();
sqlValueString.add("2012010");
sqlValueString.add("qmx10");
sqlValues.add(sqlValueString);
List sqlValueString1 =new ArrayList();
sqlValueString1.add("2012011");
sqlValueString1.add("qmx11");
sqlValues.add(sqlValueString1);
List sqlValueString2 =new ArrayList();
sqlValueString2.add("2012012");
sqlValueString2.add("qmx12");
sqlValues.add(sqlValueString2);
List sqlValueString3 =new ArrayList();
sqlValueString3.add("2012013");
sqlValueString3.add("qmx13");
sqlValues.add(sqlValueString3);
db.setSqlValue(sqlValues);
db.setSql(sql);
db.executeUpdateMore();
}
}