- 如果下面程序编译后生成Test.class,执行java Test Lily Lucy Mary Alice Rose,请写出运行结果：
class Test {
public static void main(String args[]) {
String foo = args[1];
String bar = args[2];
String baz = args[3];
System.out.println("foo:"+foo);
System.out.println("bar:"+bar);
System.out.println("baz:"+baz);
}
}
- 请输出下面程序的运行结果（若编译不过，或运行出错，直接写出错误):
class Test {
public static void main(String args[]) {
int i = 1,j = 10;
do {
if(i++ > --j) continue;
System.out.println("i = " + i + ",j = " + j);
} while (i < 5) ;
}
}
- 请输出下面程序的运行结果（若编译不过，或运行出错，直接写出错误):
class Test {
public static void main(String args[]) {
int i = 0xfffffff1;
int j = ~i;
System.out.println("j = "+j);
}
}
- 请输出下面程序的运行结果（若编译不过，或运行出错，直接写出错误):
class Test {
public static void main(String args[]) {
float f = 4.2f;
Float g = new Float(4.2f);
Double d = new Double(4.2);
System.out.println("f = g :" + (f == g));
System.out.println("g = g :" + (g == g));
System.out.println("d = f :" + (d == f));
System.out.println("d.equals(f) :" + d.equals(f));
System.out.println("d.equals(g) :" + d.equals(g));
System.out.println("g.equals(4.2):" + g.equals(4.2));
}
}
- 请输出下面程序的运行结果（若编译不过，或运行出错，直接写出错误):
public class Test {
public static int add3(Integer i) {
int val = i.intValue();
val += 3;
return i = new Integer(val);
}
public static void main(String args[]) {
Integer i = new Integer(0);
System.out.println(add3(i));
System.out.println(i.intValue());
}
}
- 请输出下面程序的运行结果（若编译不过，或运行出错，直接写出错误):
class Test {
public static void stringReplace(String text) {
text = text.replace("j","i");
}
public static void stringBufferAppend(StringBuffer text) {
text = text.append("c");
}
public static void main(String args[]) {
String txtStr = new String("java");
StringBuffer txtBuffer = new StringBuffer("java");
stringReplace(txtStr);
stringBufferAppend(txtBuffer);
System.out.println(txtStr + txtBuffer);
}
}
- 请输出下面程序的运行结果（若编译不过，或运行出错，直接写出错误):
class Test {
public static void main(String [] args) {
int [][] array = new int[3][4];
System.out.println("array.length = " + array.length);
System.out.println("array[0].length = " + array[0].length);
}
}
- 请输出下面程序的运行结果（若编译不过，或运行出错，直接写出错误):
import java.io.IOException;
class ExceptionTest {
public static void main (String args[]) {
try {
methodA();
} catch (Exception e) {
System.out.println("caught Exception");
} catch (IOException e) {
System.out.println("caught IOException");
}
}
private static void methodA () throws IOException,Exception {
throw new IOException();
}
}
- 请输出下面程序的运行结果（若编译不过，或运行出错，直接写出错误):
class Test {
public static String output = "";
public static void foo(int i) {
try {
if(i == 1) {
throw new Exception();
}
output += "1";
} catch (Exception e) {
output += "2";
return;
} finally {
output += "3";
}
output += "4";
}
public static void main(String []args) {
foo(0);
foo(1);
System.out.println(output);
}
}
- 请输出下面程序的运行结果（若编译不过，或运行出错，直接写出错误):
class Test {
public static int sValue = 2;
public static void showValue() {
int sValue = 3;
System.out.println("showValue sValue = " + sValue);
}
public static void main(String [] args) {
showValue();
System.out.println("main sValue = " + sValue);
}
}
- 请输出下面程序的运行结果（若编译不过，或运行出错，直接写出错误):
class Sub {
public void show() {
System.out.println("I am Sub show");
}
public void show(String str) {
System.out.println("show str = " + str);
}
}
class Derive extends Sub {
public void show() {
System.out.println("I am Derive show");
}
}
class Base extends Derive {
public void show(String str) {
System.out.println("Base show str = " +str);
}
public static void main(String [] args) {
Sub sub = new Base();
sub.show("me");
sub.show();
}
}
- 请输出下面程序的运行结果（若编译不过，或运行出错，直接写出错误):
interface IClick {
void onClick();
}
abstract class AClick {
public void onClick() {
System.out.println("AClick onClick");
}
}
class Base extends AClick implements IClick {
public void onClick() {
System.out.println("Base onClick");
}
public static void main(String [] args) {
IClick click = new Base();
click.onClick();
AClick aclick = new Base();
aclick.onClick();
}
}
- 请输出下面程序的运行结果（若编译不过，或运行出错，直接写出错误):
class Sub {
public void test() {
System.out.println("Sub test");
}
}
class Derive extends Sub {
private void test() {
System.out.println("Derive test");
}
public static void main(String [] args) {
Sub sub = new Derive();
sub.test();
}
}
- 请输出下面程序的运行结果（若编译不过，或运行出错，直接写出错误):
class Sub {
public Sub() {
showSelf(getClass().getName(),"null");
}
public Sub(String str) {
showSelf(getClass().getName(),str);
}
public void showSelf(String className,String str) {
System.out.println("I am " + className + ",str = " + str);
}
public static void main(String [] args) {
Sub sub = new Derive("lily");
}
}
class Derive extends Sub {
public Derive(String str) {
showSelf(getClass().getName(),str);
}
}
- 请输出下面程序的运行结果（若编译不过，或运行出错，直接写出错误):
class Sub {
public void have100M() {
System.out.println("I have 100 million");
}
}
class Derive extends Sub {
public static void main(String [] args) {
Derive derive = new Derive();
derive.have100M();
}
}
- 请输出下面程序的运行结果（若编译不过，或运行出错，直接写出错误):
abstract class Grandpa {
public abstract void have100M();
}
abstract class Father extends Grandpa {
public void dispose() {
System.out.println("Come on,My boy.Better city,Better life");
}
}
class You extends Father {
public void have100M() {
System.out.println("I have 100 million");
}
public static void main(String [] args) {
Grandpa pa = new You();
pa.have100M();
}
}
- 请指出这些getNumber方法哪些override，哪些是overload?:
class Sub {
public int getNumber() {
return 0;
}
public int getNumber(int a) {
return a;
}
}
class Derive extends Sub {
public int getNumber() {
return 1;
}
public int getNumber(int a,int b) {
return a + b;
}
public int getNumber(String a) {
return Integer.valueOf(a);
}
}
- 请输出下面程序的运行结果（若编译不过，或运行出错，直接写出错误):
class Test {
public static void main(String [] args) {
Thread thread = new Thread("glThread") {
public void run() {
System.out.println(Thread.currentThread().getName() + " is runing");
}
};
thread.run();
}
}
- 请输出下面程序的运行结果（若编译不过，或运行出错，直接写出错误):
class Test {
public static void main(String [] args) {
Runnable runnable = new Runnable() {
public void run() {
System.out.println(Thread.currentThread().getName() + " is running");
}
};
Thread thread = new Thread(runnable,"glThread");
thread.run();
thread.start();
}
}
- 请输出下面程序的运行结果（若编译不过，或运行出错，直接写出错误):
class Test {
public static void main(String [] args) {
Runnable runnable = new Runnable() {
public void run() {
System.out.println(Thread.currentThread().getName() + " is running");
}
};
Thread thread = new Thread(runnable,"glThread");
thread.start();
thread.start();
}
}
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