java面向对象考题和答案.doc

文档介绍：下面代码的输出结果是:
public class Main {
public static void main(String[] args) {
int n = 100;
int m = 200;
(f(n,m));
(n);
}
public static int f(int m, int n) {
n = m+n;
return n;
}
}

300

100

100

300
程序执行的结果是:
public class Test {
public static void main(String[] args) {
int x = 6;
Test p = new Test();
(x);
(" main: x = " + x);
}
void doStuff(int x) {
(" doStuff:x =" + x++);
}
}
doStuff:x =7
main: x = 7
:x =7
main: x = 6
:x =6
main: x = 7
:x =6
main: x = 6
:




下列代码的输出结果是:
public class Test {
public void print(char c) {
("c");
}
public void print(int i) {
("i");
}
public void print(double d) {
("d");
}
public void print(String s) {
("s");
}
public static void main(String[] args) {
Test test=new Test();
('5');
}
}




程序执行的结果是:
public class Test {
String name="Tom";
public Test(String name){
name=name;
}
public static void main(String [] args){
Test t = new Test("Jack");
();
}
}

D." "
,下列说法错误的是:




Java 中继承的特点,下列说法正确的是:

只支持单继承,不可多继承,但可以通过实现接口来达到多继承的目的
,包括父类的构造方法
,即一个类不可以继承另一个类的子类
:
class Foo {
public int a;
public Foo() {
a = 3;
}
public void addFive() {
a += 5;
}
}
class Bar extends Foo {
public int a;
public Bar() {
a = 8;
}
public void addFive() {
+= 5;
}
}
public class TestFoo {
public static void main(String[] args) {
Foo foo = new Bar();
();
("Value