4
5
8
9
Compilation fails.
An exception is thrown at runtime.
It is impossible to determine for certain.
第1题:
public class A extends Thread { A() { setDaemon(true); } public void run() { (new B()).start(); try { Thread.sleep(60000); } catch (InterruptedException x) {} System.out.println(“A done”); } class B extends Thread { public void run() { try { Thread.sleep(60000); } catch (InterruptedException x) {} System.out.println(“B done”); } } public static void main(String[] args) { (new A()).start(); } } What is the result?()
第2题:
1. public class Exception Test { 2. class TestException extends Exception {} 3. public void runTest() throws TestException {} 4. public void test() /* Point X */ { 5. runTest(); 6. } 7. } At Point X on line 4, which code is necessary to make the code compile?()
第3题:
class ThreadExcept implements Runnable { public void run() { throw new RuntimeException("exception "); } public static void main(String [] args) { new Thread(new ThreadExcept()).start(); try { int x = Integer.parseInt(args[0]); Thread.sleep(x); System.out.print("main "); } catch (Exception e) { } } } 和命令行: java ThreadExcept 1000 哪一个是结果?()
第4题:
class Top { static int x = 1; public Top(int y) { x *= 3; } } class Middle extends Top { public Middle() { x += 1; } public static void main(String [] args) { Middle m = new Middle(); System.out.println(x); } } 结果为:()
第5题:
class Work implements Runnable { Thread other; Work(Thread other) { this.other = other; } public void run() { try { other.join(); } catch (Exception e) { } System.out.print("after join "); } } class Launch { public static void main(String [] args) { new Thread(new Work(Thread.currentThread())).start(); System.out.print("after start "); } } 结果为:()
第6题:
public class TestOne { public static void main (String[] args) throws Exception { Thread.sleep(3000); System.out.println(”sleep”); } } What is the result?()
第7题:
Compilation fails.
An exception is thrown at runtime.
The code executes normally and prints “sleep”.
The code executes normally, but nothing is printed.
第8题:
Compilation fails.
An exception is thrown at runtime.
The code executes and prints “StartedComplete”.
The code executes and prints “StartedComplete0123”.
The code executes and prints “Started0l23Complete”.
第9题:
TestA
TestB
Compilation fails.
An exception is thrown at runtime.
第10题:
1
2
3
编译失败
第11题:
Throws Exception.
Catch (Exception e).
Throws RuntimeException.
Catch (TestException e).
No code is necessary.
第12题:
1
2
3
编译失败
第13题:
public class Test { public static void aMethod() throws Exception { try { throw new Exception(); } finally { System.out.println(“finally”); } } public static void main(String args[]) { try { aMethod(); } catch (Exception e) { System.out.println(“exception”); } System.out.println(“finished”); } } What is the result?()
第14题:
public class ExceptionTest { class TestException extends Exception {} public void runTest () throws TestException {} public void test () /* Point X*/ { runTest (); } } At point X on line 4, which code can be added to make the code compile?()
第15题:
public class TestOne implements Runnable { public static void main (String[] args) throws Exception { Thread t = new Thread(new TestOne()); t.start(); System.out.print(”Started”); t.join(); System.out.print(”Complete”); } public void run() { for (int i= 0; i< 4; i++) { System.out.print(i); } } } What can be a result?()
第16题:
现有: class Top { static int x=l; public Top (inty) { x*=3; } } class Middle extends Top { public Middle() {x+=1; ) public static void main (String [] args) { Middle m = new Middle(); System. out .println (x); } } 结果为:()
第17题:
public class Starter extends Thread { private int x= 2; public static void main(String[] args) throws Exception { new Starter().makeItSo(); } public Starter() { x=5; start(); } public void makeItSo() throws Exception { join(); x=x- 1; System.out.println(x); } public void run() { x *= 2; } } What is the output if the main() method is rum?()
第18题:
after join
after start
after join after start
after start after join
第19题:
No code is necessary.
throws Exception
catch ( Exception e )
throws RuntimeException
catch ( TestException e)
第20题:
4
5
8
9
Compilation fails.
An exception is thrown at runtime.
It is impossible to determine for certain.
第21题:
A done
B done
A done B done
B done A done
There is no exception that the application will print anything.
The application outputs “A done” and “B done”, in no guaranteed order.
第22题:
finally
exception finished
finally exception finished
Compilation fails.
第23题:
main
编译失败
代码运行,但没有输出
main java.lang.RuntimeException: exception
第24题:
The program prints “lava”
The program prints “java”
An error at line 7 causes compilation to fail.
Compilation succeeds but the program throws an exception.