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public static void getConnAndTableStruct() {
Connection connection = null;
PreparedStatement pstmt = null;
ResultSetMetaData rsmd = null;
try {
   // mysqlÁ¬½Ó
   //Class.forName("org.gjt.mm.mysql.Driver");
   //connection = DriverManager.getConnection("jdbc:mysql://localhost:3306/test", "root", "root");
   // oracleÁ¬½Ó
    Class.forName("oracle.jdbc.driver.OracleDriver");
    String url="jdbc:oracle:thin:@192.168.12.12:1521:db";
    connection=DriverManager.getConnection(url,"manager","manager");
   pstmt = (PreparedStatement) connection.prepareStatement("select * from A_STAT");
   pstmt.execute(); // ÕâµãÌØ±ðҪעÒâ:Èç¹ûÊÇOracle¶ø¶ÔÓÚmysql¿ÉÒÔ²»ÓüÓ.
   rsmd = (ResultSetMetaData) pstmt.getMetaData();
   //className = "User";
   //tableName = "user";
   for (int i = 1; i < rsmd.getColumnCount() + 1; i++) {
    //rsmd.getColumnName(i);
    //rsmd.getColumnClassName(i).substring(rsmd.getColumnClassName(i).lastIndexOf(".") + 1);
    System.out.println(rsmd.getColumnClassName(i));
    System.out.println(rsmd.getColumnName(i));
    System.out.println(rsmd.getColumnTypeName(i));
    System.out.println(rsmd.getPrecision(i));
    System.out.println(rsmd.getScale(i));
    System.out.println(rsmd.isNullable(i));//0 ²»ÄÜΪ¿Õ   1¿ÉÒÔΪ¿Õ
    System.out.println("=============================");
    System.out.println("=============================");
    System.out.println("=============================");
    System.out.println("


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class Tank{
 int level;
}
public class Assignment {
 public static void main(String[] args) {
  
  Tank t1 = new Tank();
  Tank t2 = new Tank();
  t1.level= 9;
  t2.level= 47;
  
  System.out.println("1:t1.l ......

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