对象数组报错“空指针”:Exception in thread "main" java.lang.NullPointerException
2014-05-02 00:49
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Student[] student = new Student[4]; [code]/*
这里虽然创建了对象数组,大小为4,但并没有为每个对象分配空间,即每个对象都是为空的。
所以如果使用student[0].age=18;
就会报空指针的错误,因为student[0]为空,即不存在这个学生,那你还问他的年龄,肯定会报错嘛。[code]/*
所以先要把对象一个一个的初始化:
for(i=0;i<4;i++){
student[0]=new Student();
}
Exception in thread "main" java.lang.NullPointerException:
所谓空指针错误是,你叫某个人去做一件事,但这个人并不存在,所以没人干这个事情,那这事就会出差错。
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