根据数据库表结构生成java类

import java.io.File;
import java.io.FileWriter;
import java.io.IOException;
import java.io.PrintWriter;
import java.sql.Connection;
import java.sql.DatabaseMetaData;
import java.sql.PreparedStatement;
import java.sql.ResultSet;
import java.sql.ResultSetMetaData;
import java.sql.SQLException;
import java.util.ArrayList;
import java.util.List;
 
import android.ConnectionFactory;
 
/**
 * 根据数据库表 生成java 实体类
 *
 * @author DLHT
 * @time 2015年9月29日下午4:13:42
 * @className GenEntityTool.java
 */
public class GenEntityTool {
    private String tablename = "test";
 
    private String[] colnames; // 列名数组
 
    private String[] colTypes; // 列名类型数组
 
    private int[] colSizes; // 列名大小数组
 
    private boolean f_util = false; // 是否需要导入包java.util.*
 
    private boolean f_sql = false; // 是否需要导入包java.sql.*
 
    public GenEntityTool() {
 
        getTablesName();
 
 
        Connection conn = null;
        PreparedStatement pstmt = null;
        ResultSetMetaData rsmd = null;
 
        conn = ConnectionFactory.getInstance().getConnection();
        String strsql = "select * from " + tablename;
        try {
            pstmt = conn.prepareStatement(strsql);
            rsmd = pstmt.getMetaData();
            int size = rsmd.getColumnCount(); // 共有多少列
            colnames = new String[size];
            colTypes = new String[size];
            colSizes = new int[size];
            for (int i = 0; i < rsmd.getColumnCount(); i++) {
                colnames[i] = rsmd.getColumnName(i + 1);
                colTypes[i] = rsmd.getColumnTypeName(i + 1);
                if (colTypes[i].equalsIgnoreCase("datetime")) {
                    f_util = true;
                }
                if (colTypes[i].equalsIgnoreCase("image")
                        || colTypes[i].equalsIgnoreCase("text")) {
                    f_sql = true;
                }
                colSizes[i] = rsmd.getColumnDisplaySize(i + 1);
            }
            String content = parse(colnames, colTypes, colSizes);
 
            try {
                FileWriter fw = new FileWriter(initcap(tablename) + ".java");
 
                PrintWriter pw = new PrintWriter(fw);
                pw.println(content);
                pw.flush();
                pw.close();
            } catch (IOException e) {
                e.printStackTrace();
            }
        } catch (SQLException e) {
            e.printStackTrace();
        } finally {
            ConnectionFactory.getInstance().closeConnection(conn, pstmt, null);
            rsmd = null;
        }
    }
 
    /**
     *    获取当前数据中的表名称
     * @methodName getTablesName
     * @time 2015年9月29日下午4:52:26
     * @packageName fanshe
     */
    public List<String> getTablesName(){
        List<String> list = null;
        Connection conn = null;
        DatabaseMetaData md = null;
        ResultSet rs = null;
        conn = ConnectionFactory.getInstance().getConnection();
        try {
            md = conn.getMetaData();
            rs = md.getTables(null, null, null, null);
            if(rs!=null&&rs.next()){
                list = new ArrayList<String>();
            }
            while (rs.next()) {
                //System.out.println("|表"+(i++)+":"+rs.getString("TABLE_NAME"));
                String tableName = rs.getString("TABLE_NAME");
                list.add(tableName);
            }
 
        } catch (SQLException e) {
            e.printStackTrace();
        } finally {
            ConnectionFactory.getInstance().closeConnection(conn, null, rs);
            md = null;
        }
        return list;
    }
 
    /**
     * 解析处理(生成实体类主体代码)
     */
    private String parse(String[] colNames, String[] colTypes, int[] colSizes) {
        StringBuffer sb = new StringBuffer();
        if (f_util) {
            sb.append("import java.util.Date;
");
        }
        if (f_sql) {
            sb.append("import java.sql.*;


");
        }
        sb.append("public class " + initcap(tablename) + " {
");
        processAllAttrs(sb);
        processAllMethod(sb);
        sb.append("}
");
 
        //markerBean(initcap(tablename), sb.toString());
 
        return sb.toString();
 
    }
 
    /**
     *  创建java 文件  将生成的属性 get/set 方法 保存到 文件中
     * markerBean
     * @time 2015年9月29日下午4:15:22
     * @packageName fanshe
     * @param className  类名称
     * @param content    类内容  包括属性 getset 方法
     */
    public void markerBean(String className, String content) {
        String folder = System.getProperty("user.dir") + "/src/fanshe/";
 
        File file = new File(folder);
        if (!file.exists()) {
            file.mkdirs();
        }
        String fileName = folder + className + ".java";
 
        try {
            File newdao = new File(fileName);
            FileWriter fw = new FileWriter(newdao);
            fw.write(content);
            fw.flush();
            fw.close();
        } catch (IOException e) {
            e.printStackTrace();
        }
    }
 
    /**
     * 生成所有的方法
     *
     * @param sb
     */
    private void processAllMethod(StringBuffer sb) {
        for (int i = 0; i < colnames.length; i++) {
            sb.append("	public void set" + initcap(colnames[i]) + "("
                    + sqlType2JavaType(colTypes[i]) + " " + colnames[i]
                    + "){
");
            sb.append("		this." + colnames[i] + "=" + colnames[i] + ";
");
            sb.append("	}
");
 
            sb.append("	public " + sqlType2JavaType(colTypes[i]) + " get"
                    + initcap(colnames[i]) + "(){
");
            sb.append("		return " + colnames[i] + ";
");
            sb.append("	}
");
        }
    }
 
    /**
     * 解析输出属性
     *
     * @return
     */
    private void processAllAttrs(StringBuffer sb) {
        for (int i = 0; i < colnames.length; i++) {
            sb.append("	private " + sqlType2JavaType(colTypes[i]) + " "
                    + colnames[i] + ";
");
 
        }
    }
 
    /**
     * 把输入字符串的首字母改成大写
     *
     * @param str
     * @return
     */
    private 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);
    }
 
    private String sqlType2JavaType(String sqlType) {
        if (sqlType.equalsIgnoreCase("bit")) {
            return "bool";
        } else if (sqlType.equalsIgnoreCase("tinyint")) {
            return "byte";
        } else if (sqlType.equalsIgnoreCase("smallint")) {
            return "short";
        } else if (sqlType.equalsIgnoreCase("int")) {
            return "int";
        } else if (sqlType.equalsIgnoreCase("bigint")) {
            return "long";
        } else if (sqlType.equalsIgnoreCase("float")) {
            return "float";
        } else if (sqlType.equalsIgnoreCase("decimal")
                || sqlType.equalsIgnoreCase("numeric")
                || sqlType.equalsIgnoreCase("real")) {
            return "double";
        } else if (sqlType.equalsIgnoreCase("money")
                || sqlType.equalsIgnoreCase("smallmoney")) {
            return "double";
        } else if (sqlType.equalsIgnoreCase("varchar")
                || sqlType.equalsIgnoreCase("char")
                || sqlType.equalsIgnoreCase("nvarchar")
                || sqlType.equalsIgnoreCase("nchar")) {
            return "String";
        } else if (sqlType.equalsIgnoreCase("datetime")) {
            return "Date";
        }
 
        else if (sqlType.equalsIgnoreCase("image")) {
            return "Blob";
        } else if (sqlType.equalsIgnoreCase("text")) {
            return "Clob";
        }
        return null;
    }
 
    public static void main(String[] args) {
        new GenEntityTool();
    }
}

获取当前数据库中 所有的表

    /**
     *    获取当前数据中的表名称
     * @methodName getTablesName
     * @time 2015年9月29日下午4:52:26
     * @packageName fanshe
     */
    public List<String> getTablesName(){
        List<String> list = null;
        Connection conn = null;
        DatabaseMetaData md = null;
        ResultSet rs = null;
        conn = ConnectionFactory.getInstance().getConnection();
        try {
            md = conn.getMetaData();
            rs = md.getTables(null, null, null, null);
            if(rs!=null&&rs.next()){
                list = new ArrayList<String>();
            }
            while (rs.next()) {
                //System.out.println("|表"+(i++)+":"+rs.getString("TABLE_NAME"));
                String tableName = rs.getString("TABLE_NAME");
                list.add(tableName);
            }
            
        } catch (SQLException e) {
            e.printStackTrace();
        } finally {
            ConnectionFactory.getInstance().closeConnection(conn, null, rs);
            md = null;
        }
        return list;
    }