DatabaseMetaData获取数据库信息和表信息(表的列名,类型,主键等)SQL java

import java.sql.*;
public class GetDBInfo
{
  public GetDBInfo()
  {
  }

  public static voidmain(String[] args)
  {
  try{
   Class.forName("com.microsoft.jdbc.sqlserver.SQLServerDriver").newInstance();
    Stringurl="jdbc:microsoft:sqlserver://GAOXIANG:1433;DataBaseName=master";
    Stringuser="daryl715";
    Stringpass="1234";
    Strings;
    Connectioncon=DriverManager.getConnection(url,user,pass);
       DatabaseMetaData dbmd=con.getMetaData();
    s =dbmd.getDriverName();
   System.out.println("驱动程序的名称是: "+s);
   System.out.println(" ");

    s =dbmd.getDatabaseProductName();
   System.out.println ("数据库名称是："+s);
   System.out.println(" ");

   ResultSet rs = dbmd.getSchemas();
   System.out.println("模式名有：");
   while(rs.next())
     System.out.print("  "+rs.getString(1));
     System.out.println();

    s = dbmd.getSQLKeywords();
   System.out.println("SQL中的关键词为: "+s);
   System.out.println(" ");

    intmax=dbmd.getMaxColumnNameLength();
   System.out.println ("列名的最大长度可以是："+max);
   System.out.println(" ");

    max =dbmd.getMaxTableNameLength();
   System.out.println ("表名的最大长度可以是："+max);
   System.out.println(" ");

    max =dbmd.getMaxColumnsInSelect();
   System.out.println ("一个select 子句所能返回的最多列数列名的最大长度可是是："+max);
   System.out.println(" ");

    max =dbmd.getMaxTablesInSelect();
   System.out.println ("一个SELECT语句最多可以访问多少个表："+max);
   System.out.println(" ");


    max =dbmd.getMaxColumnsInTable();
   System.out.println ("表中允许的最多列数："+max);
   System.out.println(" ");

    max =dbmd.getMaxConnections();
   System.out.println ("并发访问的用户个数："+max);
   System.out.println(" ");

    max =dbmd.getMaxStatementLength();
   System.out.println ("SQL语句最大允许的长度："+max);
   System.out.println(" ");

    s =dbmd.getNumericFunctions();
   System.out.println("数据库的所有数学函数的列表: "+s);
   System.out.println(" ");

    s =dbmd.getStringFunctions();
   System.out.println("数据库的所有字符串函数的列表: "+s);
   System.out.println(" ");

    s =dbmd.getSystemFunctions();
   System.out.println("数据库的所有系统函数的列表: "+s);
   System.out.println(" ");

    s =dbmd.getTimeDateFunctions();
   System.out.println("数据库的所有日期时间函数的列表: "+s);
   System.out.println(" ");

    rs =dbmd.getTypeInfo();
   while(rs.next())
     {
       System.out.print(" 数据类型名："+rs.getString(1));
       System.out.print("  数据类型："+rs.getString(2));
       System.out.print(" 精度："+   rs.getString(3));
       System.out.println(" 基数："+   rs.getString(18));
     }
     System.out.println(" ");

    s =dbmd.getURL();
   System.out.println("此数据库的url: "+s);
   System.out.println(" ");

    s =dbmd.getUserName();
   System.out.println("此数据库的用户: "+s);
   System.out.println(" ");

    String [] t = { "TABLE", "VIEW" };
    rs =dbmd.getTables(null, "HR", "%", t);
   while(rs.next()){
     System.out.print("目录名："+rs.getString(1));
     System.out.print(" 模式名："+rs.getString(2));
     System.out.print(" 表名："+rs.getString(3));
     System.out.print(" 表的类型："+rs.getString(4));
     System.out.println(" 注释："+rs.getString(5));
     }
     System.out.println(" ");

    rs =dbmd.getPrimaryKeys(null, "HR","EMPLOYEES");
   while(rs.next()){
     System.out.print("目录名："+rs.getString(1));
     System.out.print(" 模式名："+rs.getString(2));
     System.out.print(" 表名："+rs.getString(3));
     System.out.print(" 列名顺序号："+rs.getString(4));
     System.out.print(" 列名顺序号："+rs.getString(5));
     System.out.println(" 主键名："+rs.getString(6));
     }
     System.out.println(" ");

    rs = dbmd.getTableTypes();
    System.out.println(" 表的类型有：");
    while(rs.next())
      System.out.print("  "+ rs.getString(1));
      System.out.println();
      System.out.println(" ");
    rs = dbmd.getColumns(null, "HR", "EMPLOYEES", "%");
    System.out.println(" 表名 "+" 列名 "+"  数据类型"+"本地类型名"+" 列的大小"+ " 小数位数"+" 数据基数"+" 是否可空"+" 索引号");
    while(rs.next()){
     System.out.print(rs.getString(3)+" ");
     System.out.print(rs.getString(4)+" ");
     System.out.print(rs.getString(5)+" ");
     System.out.print(rs.getString(6)+" ");
     System.out.print(rs.getString(7)+" ");