下面哪个结果是正确的？（） public class Testjava { public static void main(String [] args ){ StringBuffer buf=new StringBuffer("mycode666"); buf.insert(5,"@"); System.out.println(buf.toString()); } }
举一反三
- 下面的程序段执行后，输出的结果是以下哪个选项？ StringBuffer buf=new StringBuffer("wuhan2020"); buf.insert(5, "@"); System.out.println(buf.toString());
- class Test { public static void main(String[] args) { StringBuffer sb = new StringBuffer("abcd"); sb.reverse(); System.out.println( sb.toString() ); } } 代码的输出结果是： dcba
- 中国大学MOOC: 下列代码中构造方法的返回类型是（）public class Village { Village () { System .out .println(“hiding in Village”) ; } public static void main( String args [ ]) { Village c =new Village ( ) ;}class Village { public static void main( String args [ ]) { Village c =new Village ( ) ; } Village () { System .out .println(“hiding in Village”) ; } }
- public class Example { String str = new String("Java"); StringBuffer sb = new StringBuffer("C#"); public void strcat(String str, StringBuffer sb) { str = str + " study"; sb = sb.append(" exam"); } public static void main(String args[]) { Example ex = new Example(); ex.strcat(ex.str, ex.sb); System.out.println(ex.str); System.out.println(ex.sb); }}程序的输出结果是：______
- 调用以下类D和E的main() 方法的输出结果为？class D { public static void main(String[] args) { String s1 = new String("hello"); String s2 = new String("hello"); if (s1.equals(s2)) System.out.println("equal"); else System.out.println("not equal"); }} class E { public static void main(String[] args) { StringBuffer sb1 = new StringBuffer("hello"); StringBuffer sb2 = new StringBuffer("hello"); if (sb1.equals(sb2)) System.out.println("equal"); else System.out.println("not equal"); }} A: D: equal; E: equal B: D: not equal; E: not equal C: D: equal; E: not equal D: D: not equal; E: equal