Java初级面试题
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//1.请问执行下面的程序大致会输出类似什么内容?public class TestThisToString{ public String toString(){ return "my memory location is :" + this; } public static void main(String[] args) { System.out.println(new TestThisToString()); }}
//2.myTest1() 与 myTest2() 方法,哪个的效率相对较高?为什么public class testBuilder{ public static String myTest1(){return "a"+"b"+"b"+"b"+"b"+"b"+"b"+"c" +"c" +"c" +"c" +"c" ; } public static String myTest2(){StringBuilder builder = new StringBuilder();builder.append("a").append("b").append("b").append("b").append("b").append("b").append("b".append("c").append("c").append("c").append("c").append("c") ;return builder.toString(); } public static void main(String[] args){System.out.println(myTest1());System.out.println(myTest2()); }}