test
Exception
Compilation fails.
NullPointerException
第1题:
static void test() throws RuntimeException { try { System.out.print(”test “); throw new RuntimeException(); } catch (Exception ex) { System.out.print(”exception “); } } public static void main(String[] args) { try { test(); } catch (RuntimeException ex) { System.out.print(”runtime “); } System.out.print(”end “); } What is the result?()
第2题:
public class Test { public static void main(String[] args) { String str = NULL; System.out.println(str); } } What is the result?()
第3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4题:
public static void main(String[] args) { try { args=null; args[0] = “test”; System.out.println(args[0]); } catch (Exception ex) { System.out.println(”Exception”); } catch (NullPointerException npe) { System.out.println(”NullPointerException”); } } What is the result?()
第5题:
public class Test { private static int[] x; public static void main(String[] args) { System.out.println(x[0]); } } What is the result?()
第6题:
public class TestApp{ public static void main(String[] args){ try{ int i = 0; int j = 1 / i; String myname=null; if(myname.length()>2) System.out.print(“1”); }catch(NullPointerException e){ System.out.print(“2”); } catch(Exception e){ System.out.print(“3”); } } } 上述程序运行后的输出是哪项?()
第7题:
1. class Exc0 extends Exception { } 2. class Exc1 extends Exc0 { } 3. public class Test { 4. public static void main(String args[]) { 5. try { 6. throw new Exc1(); 7. } catch (Exc0 e0) { 8. System.out.println(“Ex0 caught”); 9. } catch (Exception e) { 10. System.out.println(“exception caught”); 11. } 12. } 13. } What is the result?()
第8题:
0
null
Compilation fails.
A NullPointerException is thrown at runtime.
An ArrayIndexOutOfBoundsException is thrown at runtime.
第9题:
baz =
baz = null
baz = blue
Compilation fails.
An exception is thrown at runtime.
第10题:
end
Compilation fails.
exception end
exception test end
A Throwable is thrown by main.
An Exception is thrown by main.
第11题:
finally
exception finished
finally exception finished
Compilation fails.
第12题:
Ex0 caught
exception caught
Compilation fails because of an error at line 2.
Compilation fails because of an error at line 6.
第13题:
public static void main(String[] args) { String str = “null‟; if (str == null) { System.out.println(”null”); } else (str.length() == 0) { System.out.println(”zero”); } else { System.out.println(”some”); } } What is the result?()
第14题:
static void test() { try { String x=null; System.out.print(x.toString() +“ “); } finally { System.out.print(“finally “); } } public static void main(String[] args) { try { test(); } catch (Exception ex) { System.out.print(”exception “); } } What is the result?()
第15题:
public class Test { public static void main( String[] args) { String foo = args[1]; String bar = args[2]; String baz = args[3]; System.out.println(“baz = “ + baz); } } And the command line invocation: java Test red green blue What is the result?()
第16题:
Which code fragments will succeed in printing the last argument given on the command line to the standard output, and exit gracefully with no output if no arguments are given?() CODE FRAGMENT a: public static void main(String args[]) { if (args.length != 0) System.out.println(args[args.length-1]); } CODE FRAGMENT b: public static void main(String args[]) { try { System.out.println(args[args.length]); } catch (ArrayIndexOutOfBoundsException e) {} } CODE FRAGMENT c: public static void main(String args[]) { int ix = args.length; String last = args[ix]; if (ix != 0) System.out.println(last); } CODE FRAGMENT d: public static void main(String args[]) { int ix = args.length-1; if (ix > 0) System.out.println(args[ix]); } CODE FRAGMENT e: public static void main(String args[]) { try { System.out.println(args[args.length-1]); }catch (NullPointerException e) {} }
第17题:
class Flow { public static void main(String [] args) { try { System.out.print("before "); doRiskyThing(); System.out.print("after "); } catch (Exception fe) { System.out.print("catch "); } System.out.println("done "); } public static void doRiskyThing() throws Exception { // this code returns unless it throws an Exception } } 可能会产生下面哪两项结果?()
第18题:
public class Test { public static void main(String [] args) { System.out.println(args.length > 4 && args[4].equals(“-d”)); } } If the program is invoked using the command line: java Test One Two Three –d What is the result?()
第19题:
null
finally
null finally
Compilation fails.
finally exception
第20题:
test end
Compilation fails.
test runtime end
test exception end
A Throwable is thrown by main at runtime.
第21题:
Code fragment a.
Code fragment b.
Code fragment c.
Code fragment d.
Code fragment e.
第22题:
null
zero
some
Compilation fails.
An exception is thrown at runtime.
第23题:
NULL
Compilation fails.
The code runs with no output.
An exception is thrown at runtime.