将数据库对应的表生成对应的实体类，包含注释信息

/**
 * 
 */
package com.cloud.utils.temp;

import java.io.File;
import java.io.FileWriter;
import java.io.PrintWriter;
import java.sql.Connection;
import java.sql.DatabaseMetaData;
import java.sql.DriverManager;
import java.sql.ResultSet;
import java.text.SimpleDateFormat;
import java.util.Date;
import javax.swing.filechooser.FileSystemView;
/**
 * @author liuwei
 *
 */
public class GenEntityTable {
	
	/**
	 * 这里是Oracle连接方法
	 *private static final String driver = "oracle.jdbc.driver.OracleDriver";
	 *private static final String url = "jdbc:oracle:thin:@localhost:1521:orcl";
	 *private static final String uid = "system";
	 *private static final String pwd = "sys";
	 *这里是SQL Server连接方法
	 *private static final String url = "jdbc:sqlserver://localhost:1433;DateBaseName=数据库名";
	 *private static final String driver = "com.microsoft.sqlserver.jdbc.SQLServerDriver"
	 *private static final String uid = "sa";
	 *private static final String pwd = "sa";
	 *
	 *
	 * 这里是MySQL连接方法
	 */
	private static final String driver="com.mysql.jdbc.Driver";
	private static final String pwd="root";
	private static final String user="root";
	private static final String url = "jdbc:mysql://localhost/eastbeidou" + "?user=" + user + "&password=" + pwd + "&useUnicode=true&characterEncoding=UTF-8";
	private static String tablename = "t_user";// 表名
	
	private static String setpackage="com.sxdl.vo";//你的实体类所在的包的位置
	
	private static Connection getConnection=null;
	
	public static void main(String[] args) {
		FileSystemView fsv=FileSystemView.getFileSystemView();
		String path=fsv.getHomeDirectory().toString();//获取当前用户桌面路径
		getConnection=getConnections();
		try {
			DatabaseMetaData dbmd=getConnection.getMetaData();
		    ResultSet resultSet = dbmd.getTables(null, "%", "%", new String[] { "TABLE" });
		    while (resultSet.next()) {
		    	String tableName=resultSet.getString("TABLE_NAME");
		    	//System.out.println(tableName);
		    	if(tablename.equals(tableName)){//这里干掉IF可对库里面所有表直接生成
		    		//ResultSet rs =getConnection.getMetaData().getColumns(null, getXMLConfig.getSchema(),tableName.toUpperCase(), "%");//其他数据库不需要这个方法的，直接传null，这个是oracle和db2这么用
		    		ResultSet rs1 = dbmd.getColumns(null, "%", tableName, "%");
		    		ResultSet rs2 = dbmd.getColumns(null, "%", tableName, "%");
		    		File directory = new File(path+"\\"+ initcap(tablename)+".java");
					FileWriter fw = new FileWriter(directory);
					PrintWriter pw = new PrintWriter(fw);
					if(setpackage==null || setpackage==""){
						pw.write("package com.sxdl.vo;\r\n");
					}else{
						pw.write("package "+setpackage+";\r\n");
					}
					pw.write("\r\n");
					pw.write("   /**\r\n");
					pw.write("    * " + tablename + " 实体类\r\n");
					pw.write("    * " + getDate()+ " Lw\r\n");
					pw.write("    */ \r\n");
					pw.write("\r\npublic class " + initcap(tablename) + "{\r\n");
					System.out.println();
					System.out.println(tablename+"表信息：");
					System.out.println();
		    		while(rs1.next()){
		    			System.out.println("private " +sqlType2JavaType(rs1.getString("TYPE_NAME"))+"	"+rs1.getString("COLUMN_NAME")+";");
						if (directory.exists()) {
						} else {
							directory.createNewFile();
						}
						String type = sqlType2JavaType(rs1.getString("TYPE_NAME"));
						String name = rs1.getString("COLUMN_NAME");
						String remark = rs1.getString("REMARKS");
						createPrtype(pw,type,name,remark);
		    		}
		    		//提供Get和Set方法
					pw.write("\r\n");
		    		while(rs2.next()){
		    			String name = rs2.getString("COLUMN_NAME");
		    			String type = rs2.getString("TYPE_NAME");
		    			createMethod(pw,type,name);
		    		}
		    		pw.write("}\r\n");
		    		
	    			pw.flush();
					pw.close();
					System.out.println();
					System.out.println();
					System.out.println("=====注意☆信息=====");
					System.out.println();
					if(setpackage==null || setpackage=="" ||setpackage.equals("com.sxdl.vo")){
						System.out.println(" 生成成功、文件在你的桌面。但你没有设置你的实体类所在的包的位置，有可能package会出错！");
						System.out.println("找到私有属性“setpackage”来设置，默认为：com.lw.vo;");
						System.out.println();
					}else{
						System.out.println("	生成成功！文件在你的桌面。");
						System.out.println();
					}
		    	}
		    }
		} catch (Exception e) {
			e.printStackTrace();
		}
	
	}
	
	/**生成属性*/
	public static void createPrtype(PrintWriter pw,String type,String name,String remark){
		if(remark!=null && !"".equals(remark)){
			pw.write("\t/**\r\n");
			pw.write("\t*"+remark+"\r\n");
			pw.write("\t*/\r\n");
		}else{
			pw.write("\t//"+name+"\r\n");
		}
		pw.write("\tprivate " +sqlType2JavaType(type)+"	"+name+";\r\n");
	}
	
	/**生成方法*/
	public static void createMethod(PrintWriter pw,String type,String name){
		pw.write("\tpublic void set" + initcap(name) + "("+ sqlType2JavaType(type) + " " + name+ "){\r\n");
		pw.write("\t\tthis." + name + "=" + name + ";\r\n");
		pw.write("\t}\r\n");
		pw.write("\tpublic " + sqlType2JavaType(type) + " get"+ initcap(name) + "(){\r\n");
		pw.write("\t\treturn " + name + ";\r\n");
		pw.write("\t}\r\n");
		pw.write("\r\n");
	}
	
	
	// 创建数据库连接
	public static Connection getConnections() {
		try {
			Class.forName(driver);
			getConnection = DriverManager.getConnection(url, user, pwd);
		} catch (Exception e) {
			e.printStackTrace();
		}
		return getConnection;
	}

	// 将单词字母首字母改为大写
	private static String initcap(String str) {
		char[] ch = str.toCharArray();
		if (ch[0] >= 'a' && ch[0] <= 'z') {
			ch[0] = (char) (ch[0] - 32);
		}
		return new String(ch);
	}

	// 判断属性类型
	public static String sqlType2JavaType(String sqlType) {
		String str = null;
		if (sqlType.equalsIgnoreCase("bit")) {
			str = "boolean";
		} else if (sqlType.equalsIgnoreCase("tinyint")) {
			str = "byte";
		} else if (sqlType.equalsIgnoreCase("smallint")) {
			str = "short";
		} else if (sqlType.equalsIgnoreCase("int")) {
			str = "int";
		} else if (sqlType.equalsIgnoreCase("bigint")) {
			str = "long";
		} else if (sqlType.equalsIgnoreCase("float")) {
			str = "float";
		} else if (sqlType.equalsIgnoreCase("decimal") || sqlType.equalsIgnoreCase("numeric")
				|| sqlType.equalsIgnoreCase("real") || sqlType.equalsIgnoreCase("money")
				|| sqlType.equalsIgnoreCase("smallmoney")) {
			str = "double";
		} else if (sqlType.equalsIgnoreCase("varchar") || sqlType.equalsIgnoreCase("char")
				|| sqlType.equalsIgnoreCase("nvarchar") || sqlType.equalsIgnoreCase("nchar")
				|| sqlType.equalsIgnoreCase("text")) {
			str = "String";
		} else if (sqlType.equalsIgnoreCase("datetime")) {
			str = "String";
		} else if (sqlType.equalsIgnoreCase("image")) {
			str = "Blod";
		}
		return str;
	}

	// 获取格式化后的时间
	private static String getDate() {
		String time = null;
		SimpleDateFormat sdf = new SimpleDateFormat("yyyy-MM-dd HH:mm:ss");
		time = sdf.format(new Date());
		return time;
	}

}