Java使用MySQL

this.pstmt=pstmt; 
    this.rs=rs; 
    try{ 
Class.forName("com.mysql.jdbc.Driver"); 
String url="jdbc:mysql://localhost/mydatabase?useUnicode=true&characterEncoding=UTF-8"; 
    conn=DriverManager.getConnection(url,"root","root"); 
    pstmt=conn.createStatement(); 
    rs=pstmt.executeQuery("select*from dictionary"); 
你这里的 this.rs还是null，所以，会抛nullPoint，应该把this.rs=rs; 这句放到rs=pstmt.executeQuery("select*from dictionary"); 
的后面， 

还有，mdd.rs.getString("word")==tfind.getText()这个判断很有问题，String类的判断，这里最好用 
mdd.rs.getString("word".equals(tfind.getText());