多项选择题
public class NamedCounter {
private final String name;
private int count;
public NamedCounter(String name) { this.name = name; }
public String getName() { return name; }
public void increment() { coount++; }
public int getCount() { return count; }
public void reset() { count = 0; } }
Which three changes should be made to adapt this class to be used safely by multiple threads? ()
A. declare reset() using the synchronized keyword
B. declare getName() using the synchronized keyword
C. declare getCount() using the synchronized keyword
D. declare the constructor using the synchronized keyword
E. declare increment() using the synchronized keyword
相关考题
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单项选择题
public class TwoThreads { private static Object resource = new Object(); private static void delay(long n) { try { Thread.sleep(n); } catch (Exception e) { System.out.print(”Error “); } } public static void main(String[] args) { System.out.print(”StartMain “); new Thread1().start(); delay(1000); Thread t2 = new Thread2(); t2.start(); delay(1000); t2.interrupt delay(1000); System.out.print(”EndMain “); } static class Thread 1 extends Thread { public void run() { synchronized (resource) { System.out.print(”Startl “); delay(6000); System.out.print(”End1 “); } } } static class Thread2 extends Thread { public void run() { synchronized (resource) { System.out.print(”Start2 “); delay(2000); System.out.print(”End2 “); } } } } Assume that sleep(n) executes in exactly m milliseconds, and all other code executes in an insignificant amount of time. What is the output if the main() method is run?()
A. Compilation fails.
B. Deadlock occurs.
C. StartMain Start1 Error EndMain End1
D. StartMain Start1 EndMain End1 Start2 End2
E. StartMain Start1 Error Start2 EndMain End2 End1
F.StartMain Start1 EndMain End1 Start2 Error End2 -
单项选择题
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?()
A. Compilation fails.
B. An exception is thrown at runtime.
C. The code executes and prints “StartedComplete”.
D. The code executes and prints “StartedComplete0123”.
E. The code executes and prints “Started0l23Complete”. -
单项选择题
public class TestOne { public static void main (String[] args) throws Exception { Thread.sleep(3000); System.out.println(”sleep”); } } What is the result?()
A. Compilation fails.
B. An exception is thrown at runtime.
C. The code executes normally and prints “sleep”.
D. The code executes normally, but nothing is printed.
