添加属性:
1.正在使用的数据库名称:
usingDB=mysql
2.获取环境开发目录(路径):
srcPath=D:\javaEclipse\java_282_SORM\src
3.从表结构生成数据结构建立联系的包名:
poPackage=com.han.po
po的意思是Persistence Object持久化对象
4:创建与poPackage对应的项目包

//------------管理配置信息---------------------
package com.han.sorm.bean;
/**

• 管理配置信息
  */
  public class Configuration {//配置
  //配置信息(db.properties)
  private String driver;//驱动类
  private String url;//资源;JDBC的url
  private String user;//数据库的用户名
  private String pwd;//数据库的密码
  private String usingDB;//正在使用的数据库
  private String srcPath;//路径;项目的源码路径
  private String poPackage;//连接包;扫描生成java类的包;(po的意思是Persistence object持久化对象)
  //构造器
  public Configuration() {
  super();
  }
  public Configuration(String driver, String url, String user, String pwd,
  String usingDB, String srcPath, String poPackage) {
  super();
  this.driver = driver;
  this.url = url;
  this.user = user;
  this.pwd = pwd;
  this.usingDB = usingDB;
  this.srcPath = srcPath;
  this.poPackage = poPackage;
  }

  //set与get
  public String getDriver() {
  return driver;
  }
  public void setDriver(String driver) {
  this.driver = driver;
  }
  public String getUrl() {
  return url;
  }
  public void setUrl(String url) {
  this.url = url;
  }
  public String getUser() {
  return user;
  }
  public void setUser(String user) {
  this.user = user;
  }
  public String getPwd() {
  return pwd;
  }
  public void setPwd(String pwd) {
  this.pwd = pwd;
  }
  public String getUsingDB() {
  return usingDB;
  }
  public void setUsingDB(String usingDB) {
  this.usingDB = usingDB;
  }
  public String getSrcPath() {
  return srcPath;
  }
  public void setSrcPath(String srcPath) {
  this.srcPath = srcPath;
  }
  public String getPoPackage() {
  return poPackage;
  }
  public void setPoPackage(String poPackage) {
  this.poPackage = poPackage;
  }
  }
  //--------------连接对象的管理------------------
  package com.han.sorm.core;

import java.io.IOException;
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 com.han.sorm.bean.Configuration;

/**

• DBManager数据库管理器

• 根据配置信息,维持连接对象的管理(增加连接池功能)
  */
  public class DBManager {
  private static Configuration conf;

  static{//静态代码块
  Properties pros = new Properties();//读取配置文件信息
  //加载输入流
  try {
  pros.load(Thread.currentThread().getContextClassLoader().getResourceAsStream(“db.properties”));
  //load加载获取输入流;Thread.currentThread当前线程;getContextClassLoader获得上下文类加载器;getResourceAsStream获取作为流的资源
  } catch (IOException e) {
  e.printStackTrace();
  }
  //构建对象
  conf = new Configuration();
  //获取资源
  conf.setDriver(pros.getProperty(“driver”));
  conf.setPoPackage(pros.getProperty(“poPackage”));
  conf.setPwd(pros.getProperty(“pwd”));
  conf.setSrcPath(pros.getProperty(“srcPath”));
  conf.setUrl(pros.getProperty(“url”));
  conf.setUser(pros.getProperty(“user”));
  conf.setUsingDB(pros.getProperty(“usingDB”));
  }
  //建立mysql连接
  public static Connection getConn(){
  try {
  //加载驱动类
  Class.forName(conf.getDriver());
  //连接数据库
  return DriverManager.getConnection(conf.getUrl(),conf.getUser(),
  conf.getPwd());//直接建立连接;后期增加连接池处理,提高效率!
  } catch (Exception e) {
  e.printStackTrace();
  return null;
  }
  }

  //封装关闭方法
  public static void close(ResultSet rs){
  try {
  if(rs!=null){
  rs.close();//关闭
  }
  } catch (Exception e) {
  e.printStackTrace();
  }
  }
  public static void close(Statement ps){
  try {
  if(ps!=null){
  ps.close();//关闭
  }
  } catch (SQLException e) {
  e.printStackTrace();
  }
  }
  public static void close(Connection conn){
  try {
  if(conn!=null){
  conn.close();//关闭
  }
  } catch (SQLException e) {
  e.printStackTrace();
  }
  }
  public static void close(ResultSet rs,Statement ps,Connection conn){
  //关闭遵循先进后关原则;一定要分开关闭,这样出现异常不影响后面的程序执行
  try {
  if(rs!=null){
  rs.close();//关闭
  }
  } catch (Exception e) {
  e.printStackTrace();
  }
  try {
  if(ps!=null){
  ps.close();//关闭
  }
  } catch (SQLException e) {
  e.printStackTrace();
  }
  try {
  if(conn!=null){
  conn.close();//关闭
  }
  } catch (SQLException e) {
  e.printStackTrace();
  }
  }
  }
  //--------------存储表结构的信息--------
  package com.han.sorm.bean;

import java.util.List;
import java.util.Map;

/**

• 存储表结构的信息

/
public class TableInfo {//表信息
/*
* 表名
/
private String tname;
/*
* 所有字段的信息
/
private Map<String,ColumnInfo> columns;
/*
* 唯一主键(目前我们只能处理表中有且只有一个主键的情况)
*/
private ColumnInfo onlyPriKey;

private List<ColumnInfo> priKeys;//如果联合主键,则在这里存储//set与getpublic List<ColumnInfo> getPriKeys() {return priKeys;
}
public void setPriKeys(List<ColumnInfo> priKeys) {this.priKeys = priKeys;
}
public String getTname() {return tname;
}
public void setTname(String tname) {this.tname = tname;
}
public Map<String, ColumnInfo> getColumns() {return columns;
}
public void setColumns(Map<String, ColumnInfo> columns) {this.columns = columns;
}
public ColumnInfo getOnlyPriKey() {return onlyPriKey;
}
public void setOnlyPriKey(ColumnInfo onlyPriKey) {this.onlyPriKey = onlyPriKey;
}//构造器
public TableInfo(String tname, List<ColumnInfo> priKeys, Map<String, ColumnInfo> columns) {super();this.tname = tname;this.columns = columns;this.priKeys = priKeys;
}
public TableInfo() {super();
}
public TableInfo(String tname, Map<String, ColumnInfo> columns,List<ColumnInfo> priKeys) {super();this.tname = tname;this.columns = columns;this.priKeys = priKeys;
}

}
//--------------上下文管理---------------
package com.han.sorm.core;

import java.sql.Connection;
import java.sql.DatabaseMetaData;
import java.sql.ResultSet;
import java.sql.SQLException;
import java.util.ArrayList;
import java.util.HashMap;
import java.util.Map;

import com.han.sorm.bean.ColumnInfo;
import com.han.sorm.bean.TableInfo;

/**

• 备注:这段代码不用细研究 ;用时直接拷贝
  *TableContext表的上下文
  负责获取管理数据库所有表结构和类结构的关系,并可以根据表结构生成类结构
  /
  public class TableContext {
  /

  • 表名为key,表信息对象为value;数据库的表结构都存放这里
    /
    public static Map<String,TableInfo> tables = new HashMap<String,TableInfo>();
    /*
  • 将po的class对象和表信息对象关联起来,便于使用
    */
    public static Map<Class,TableInfo> poClassTableMap = new HashMap<Class, TableInfo>();

  private TableContext(){}

  static{
  try {
  //初始化获得表的信息
  Connection con = DBManager.getConn();//获取Connection对象
  //DatabaseMetaData(它封装了数据库的所有信息)
  DatabaseMetaData dbmd = con.getMetaData(); // 获取源数据库信息

   	ResultSet tableRet = dbmd.getTables(null, "%", "%", new String[]{"TABLE"});//获取表的所有信息while(tableRet.next()){String tableName = (String) tableRet.getObject("TABLE_NAME");TableInfo ti = new TableInfo(tableName,new ArrayList<ColumnInfo>(),new HashMap<String, ColumnInfo>());tables.put(tableName, ti);ResultSet set = dbmd.getColumns(null, "%", tableName, "%");//查询表中的所有字段//循环while(set.next()){ColumnInfo ci = new ColumnInfo(set.getString("COLUMN_NAME"),set.getString("TYPE_NAME"),0);//获取字段ti.getColumns().put(set.getString("COLUMN_NAME"), ci);//填充到表信息里面}//获取主键ResultSet set2 = dbmd.getColumns(null, "%", tableName, "%");//查询表中的所有字段	while(set2.next()){ColumnInfo ci2 = (ColumnInfo)ti.getColumns().get(set2.getObject("COLUMN_NAME"));ci2.setKeyType(1);//设置为主键类型ti.getPriKeys().add(ci2);//存放键信息}if(ti.getPriKeys().size()>0){//取唯一主键,方便使用.如果是联合主键则设为空ti.setOnlyPriKey(ti.getPriKeys().get(0));}}} catch (SQLException e) {e.printStackTrace();}
  

  }
  public static void main(String[] args) {
  Map<String,TableInfo> tables= TableContext.tables;
  System.out.println(tables);
  }
  }