JDBC增删改查方法小记（2个表相关联）

import java.sql.Connection;
import java.sql.DriverManager;
import java.sql.ResultSet;
import java.sql.SQLException;
import java.sql.Statement;
import java.util.Properties;

import org.springframework.core.io.support.PropertiesLoaderUtils;

public class SingletonConn
{
private Connection connection = null;
private Statement statement = null;
private ResultSet resultSet = null;
private static String DBClassName = null;
private static String DBUrl = null;
private static String DBUser = null;
private static String DBPassword  = null;

private static SingletonConn instance = null;

protected SingletonConn()
{
}

static
{
try
{
Properties props = PropertiesLoaderUtils.loadAllProperties("com/ioif/wha/database/database.properties");
DBClassName = props.getProperty("DriverClass");
DBUrl = props.getProperty("URL");
DBUser = props.getProperty("User");
DBPassword = props.getProperty("Password");

Class.forName(DBClassName);
}
catch (Exception e)
{
e.printStackTrace();
}
}

public static synchronized SingletonConn getInstance()
{
if(instance == null)
{
instance = new SingletonConn();
}
return instance;
}

public synchronized Connection getConnection() throws SQLException
{
//仅当connection失效时才重新获取
if (connection == null || connection.isValid(10) == false)
{
connection = DriverManager.getConnection(DBUrl, DBUser, DBPassword);
}
return connection;
}

private synchronized void getStatement() throws SQLException
{
getConnection();
//仅当statement失效时才重新创建
if (statement == null || statement.isClosed() == true)
{
statement = connection.createStatement(
ResultSet.TYPE_SCROLL_INSENSITIVE,
ResultSet.CONCUR_READ_ONLY);
}
}

public synchronized void close() throws SQLException
{
if (resultSet != null)
{
resultSet.close();
resultSet = null;
}
if (statement != null)
{
statement.close();
statement = null;
}
if (connection != null)
{
connection.close();
connection = null;
}
}

public synchronized ResultSet executeQuery(String sql) throws SQLException
{
getStatement();
if (resultSet != null && resultSet.isClosed() == false)
{
resultSet.close();
}
resultSet = null;
resultSet = statement.executeQuery(sql);
return resultSet;
}

public synchronized int executeUpdate(String sql) throws SQLException
{
int result = 0;
getStatement();
result = statement.executeUpdate(sql);
return result;
}

}

import java.sql.Connection;
import java.sql.PreparedStatement;
import java.sql.ResultSet;
import java.sql.SQLException;
import java.util.ArrayList;
import java.util.HashSet;
import java.util.List;

import com.ioif.wha.database.Data;

public class DBUtill {

Data d;
static List<Data> list = new ArrayList<Data>();
static String tabName;
private static Connection conn = null;
private static PreparedStatement ps = null;

public static List getDate() {
list.clear();
try {
ResultSet rs = SingletonConn
.getInstance()
.executeQuery(
"select * from vav_page page,vav_card card where page.id=card.id");
while (rs.next()) {
int id = rs.getInt("id");
int type = rs.getInt("type");
int position = rs.getInt("position");
String name = rs.getString("name");
String url = rs.getString("url");
String imageUrl = rs.getString("imageUrl");
System.out.println("id---" + id + "---position---" + position
+ "---type---" + type + "---name---" + name
+ "---url---" + url + "---imageurl---" + imageUrl);
Data d = new Data(id, position, type, name, url, imageUrl);
list.add(d);
}
} catch (Exception e) {
e.printStackTrace();
}
return list;
}

public static boolean creatTable() {
boolean flag = false;
if (tabName == null || tabName.equals("")) {
return false;
}
System.out.println("Creating tables...");
String sql = "CREATE TABLE " + tabName + "_page "
+ "( id INTEGER auto_increment not null, "
+ " position INTEGER, " + " type INTEGER, "
+ " PRIMARY KEY( id ))";
String sql2 = "CREATE TABLE " + tabName + "_card" + "("
+ "id INTEGER auto_increment NOT NULL, "
+ "name VARCHAR(255), " + "url VARCHAR(255), "
+ "imageUrl VARCHAR(255)," + "PRIMARY KEY(id), "
+ "constraint fk_" + tabName + " foreign key(id) references "
+ tabName + "_page(id)" + ")";
try {
SingletonConn.getInstance().executeUpdate(sql);
SingletonConn.getInstance().executeUpdate(sql2);
System.out.println("Created tables...");
flag = true;
} catch (SQLException e) {
// TODO Auto-generated catch block
e.printStackTrace();
}
return flag;
}

public static List getTabName() {
List<String> list = new ArrayList<String>();
List<String> listWithoutDup;
// 获取表名
ResultSet rs;
try {
rs = SingletonConn.getInstance().getConnection().getMetaData()
.getTables("", "", "", null);
while (rs.next()) {
String Name = rs.getString("TABLE_NAME");
int i = Name.indexOf("_");
String tbName = Name.substring(0,i);
System.out.println(tbName);
list.add(tbName);
}
} catch (SQLException e) {
// TODO Auto-generated catch block
e.printStackTrace();
}
listWithoutDup = new ArrayList<String>(new HashSet<String>(list));
return listWithoutDup;
}

public static void setTabName(String Name) {
tabName = Name;
}

public static boolean InsertDate(List<Data> list) {
boolean flag = false;
System.out.println("Inserting tables...");
if (tabName == null || tabName.equals("")) {
return false;
}
try {
conn = SingletonConn.getInstance().getConnection();
conn.setAutoCommit(false);
for (int i = 0; i < list.size(); i++) {
int positon = list.get(i).getPosition();
int type = list.get(i).getType();
String name = list.get(i).getName();
String url = list.get(i).getUrl();
String imageUrl = list.get(i).getImageUrl();

String sql = "insert into " + tabName
+ "_page(position,type) values(?,?)";

ps = conn.prepareStatement(sql);
ps.setInt(1, positon);
ps.setInt(2, type);
ps.executeUpdate();

sql = "select id from "+tabName+"_page where position=? and type =?";
ps = conn.prepareStatement(sql);
ps.setInt(1, positon);
ps.setInt(2, type);
ResultSet rs = ps.executeQuery();
int id = 0;
while(rs.next()){
id = rs.getInt("id");
}

sql = "insert into " + tabName
+ "_card(id,name,url,imageUrl) values(?,?,?,?)";
ps = conn.prepareStatement(sql);
ps.setInt(1, id);
ps.setString(2, name);
ps.setString(3, url);
ps.setString(4, imageUrl);
ps.executeUpdate();
ps.close();

conn.commit();
}
System.out.println("Inserted tables...");
flag = true;
} catch (SQLException e) {
// TODO Auto-generated catch block
try {
conn.rollback();
} catch (SQLException e1) {
// TODO Auto-generated catch block
e1.printStackTrace();
}
e.printStackTrace();
}
return flag;
}

public static boolean Update(Data data){
boolean flag = false;
System.out.println("Updating tables...");
if (tabName == null || tabName.equals("")) {
return false;
}
try{
conn = SingletonConn.getInstance().getConnection();
String sql = "update "+tabName+"_page set position=?,type=? where id=?";
ps = conn.prepareStatement(sql);
ps.setInt(1, data.getPosition());
ps.setInt(2, data.getType());
ps.setInt(3, data.getId());
ps.executeUpdate();
ps.close();

sql = "update "+tabName+"_card set name=?,url=?,imageUrl=? where id=?";
ps = conn.prepareStatement(sql);
ps.setString(1, data.getName());
ps.setString(2, data.getUrl());
ps.setString(3, data.getImageUrl());
ps.setInt(4, data.getId());
ps.executeUpdate();
ps.close();

conn.commit();
System.out.println("Updated tables...");
flag = true;
}catch(Exception e){
try {
conn.rollback();
} catch (SQLException e1) {

4000
// TODO Auto-generated catch block
e1.printStackTrace();
}
e.printStackTrace();
}
return flag;
}

public static boolean Delete(int id){
boolean flag = false;
System.out.println("Deleting tables...");
if (tabName == null || tabName.equals("")) {
return false;
}
try{
String sql = "delete from "+tabName+"_card where id="+id;
SingletonConn.getInstance().executeUpdate(sql);
sql = "delete from "+tabName+"_page where id="+id;
SingletonConn.getInstance().executeUpdate(sql);
System.out.println("Deleted tables...");
flag = true;
}catch(Exception e){
e.printStackTrace();
}
return flag;
}

}