Java常用内置注解用法分析

public class ch11_2 {
  public static void main( String args[] ) {
    @SuppressWarnings("unused")
    int a;          // A处不会产生编译告警
    String bString = "ok";  // B处会产生编译告警
    System.out.println("@SuppressWarnings description");
  }
}

public class ch11_3 {
  public static void main(String[] args) {
   ch11_3_1.test1();   // 这里会提示警告信息
   ch11_3_1.test2();
  }
}
class ch11_3_1{
  @Deprecated
  public static void test1(){
   System.out.println("test1 method is deprecated");
  }
  public static void test2(){
   System.out.println("test1 method is pray");
  }
}