实训JAVA语言设计——程序查错

查错：

11

1. public class WhatHappens {

2. public static void main(String[] args) {

3. StringBuffer[] stringBuffers = new StringBuffer[10];

4. for (int i = 0; i < stringBuffers.length; i ++) {

5. stringBuffers[i].append("StringBuffer at index " + i);

6. }

7. }

8. }

Answer:程序在第定义了数组StringBuffers[]，但在使用数组StringBuffers对象时没有初始化，要初始化后才能使用。如下第5行为对数组对象初始化

1. public class ThisHappens {

2. public static void main(String[] args) {

3. StringBuffer[] stringBuffers = new StringBuffer[10];

4. for (int i = 0; i < stringBuffers.length; i ++) {

5.  stringBuffers[i] = new StringBuffer();

6. stringBuffers[i].append("StringBuffer at index " + i);

7. }

8. }

9. }