The document appears to be a log of exceptions encountered during the execution of Java code. It traces the stack trace of a NullPointerException thrown when loading dialog settings. The exception occurs at the initialization of the PackageExplorerPart class in Eclipse.

1. Java - Quiz
Ganesh Samarthyam
ganesh@codeops.tech

2. Programmer’s world :)
java.lang.NullPointerException
at org.eclipse.jface.dialogs.DialogSettings.load(DialogSettings.java:278)
at org.eclipse.jface.dialogs.DialogSettings.load(DialogSettings.java:306)
at org.eclipse.jface.dialogs.DialogSettings.load(DialogSettings.java:247)
at org.eclipse.jface.dialogs.DialogSettings.load(DialogSettings.java:264)
at org.eclipse.ui.plugin.AbstractUIPlugin.loadDialogSettings(AbstractUIPlugin.java:411)
at org.eclipse.ui.plugin.AbstractUIPlugin.getDialogSettings(AbstractUIPlugin.java:232)
at org.eclipse.jdt.internal.ui.JavaPlugin.getDialogSettingsSection(JavaPlugin.java:1012)
at org.eclipse.jdt.internal.ui.packageview.PackageExplorerPart.<init>(PackageExplorerPart.java:436)
at sun.reflect.NativeConstructorAccessorImpl.newInstance0(Native Method)
at sun.reflect.NativeConstructorAccessorImpl.newInstance(Unknown Source)
at sun.reflect.DelegatingConstructorAccessorImpl.newInstance(Unknown Source)
at java.lang.reflect.Constructor.newInstance(Unknown Source)
at java.lang.Class.newInstance0(Unknown Source)
at java.lang.Class.newInstance(Unknown Source)
at org.eclipse.core.internal.registry.osgi.RegistryStrategyOSGI.createExecutableExtension(RegistryStrategyOSGI.java:170)
at org.eclipse.core.internal.registry.ExtensionRegistry.createExecutableExtension(ExtensionRegistry.java:867)
at org.eclipse.core.internal.registry.ConfigurationElement.createExecutableExtension(ConfigurationElement.java:243)
at org.eclipse.core.internal.registry.ConfigurationElementHandle.createExecutableExtension(ConfigurationElementHandle.java:51)
at org.eclipse.ui.internal.WorkbenchPlugin$1.run(WorkbenchPlugin.java:267)
at org.eclipse.swt.custom.BusyIndicator.showWhile(BusyIndicator.java:70)
at org.eclipse.ui.internal.WorkbenchPlugin.createExtension(WorkbenchPlugin.java:263)
at org.eclipse.ui.internal.registry.ViewDescriptor.createView(ViewDescriptor.java:63)
at org.eclipse.ui.internal.ViewReference.createPartHelper(ViewReference.java:328)
at org.eclipse.ui.internal.ViewReference.createPart(ViewReference.java:230)
at org.eclipse.ui.internal.WorkbenchPartReference.getPart(WorkbenchPartReference.java:594)
at org.eclipse.ui.internal.Perspective.showFastView(Perspective.java:2053)
at org.eclipse.ui.internal.Perspective.setActiveFastView(Perspective.java:1835)
at org.eclipse.ui.internal.Perspective.setActiveFastView(Perspective.java:1848)
at org.eclipse.ui.internal.Perspective.toggleFastView(Perspective.java:2241)
at org.eclipse.ui.internal.WorkbenchPage.toggleFastView(WorkbenchPage.java:3824)
at org.eclipse.ui.internal.ShowFastViewContribution.showView(ShowFastViewContribution.java:157)
at org.eclipse.ui.internal.ShowFastViewContribution.access$1(ShowFastViewContribution.java:155)
at org.eclipse.ui.internal.ShowFastViewContribution$3.widgetSelected(ShowFastViewContribution.java:138)
at org.eclipse.swt.widgets.TypedListener.handleEvent(TypedListener.java:228)
at org.eclipse.swt.widgets.EventTable.sendEvent(EventTable.java:84)
at org.eclipse.swt.widgets.Widget.sendEvent(Widget.java:1003)
at org.eclipse.swt.widgets.Display.runDeferredEvents(Display.java:3823)
at org.eclipse.swt.widgets.Display.readAndDispatch(Display.java:3422)
at org.eclipse.ui.internal.Workbench.runEventLoop(Workbench.java:2382)
at org.eclipse.ui.internal.Workbench.runUI(Workbench.java:2346)
at org.eclipse.ui.internal.Workbench.access$4(Workbench.java:2198)
at org.eclipse.ui.internal.Workbench$5.run(Workbench.java:493)
at org.eclipse.core.databinding.observable.Realm.runWithDefault(Realm.java:288)
at org.eclipse.ui.internal.Workbench.createAndRunWorkbench(Workbench.java:488)
at org.eclipse.ui.PlatformUI.createAndRunWorkbench(PlatformUI.java:149)
at org.eclipse.ui.internal.ide.application.IDEApplication.start(IDEApplication.java:113)
at org.eclipse.equinox.internal.app.EclipseAppHandle.run(EclipseAppHandle.java:193)
at org.eclipse.core.runtime.internal.adaptor.EclipseAppLauncher.runApplication(EclipseAppLauncher.java:110)
at org.eclipse.core.runtime.internal.adaptor.EclipseAppLauncher.start(EclipseAppLauncher.java:79)
at org.eclipse.core.runtime.adaptor.EclipseStarter.run(EclipseStarter.java:382)
at org.eclipse.core.runtime.adaptor.EclipseStarter.run(EclipseStarter.java:179)
at sun.reflect.NativeMethodAccessorImpl.invoke0(Native Method)
at sun.reflect.NativeMethodAccessorImpl.invoke(Unknown Source)
at sun.reflect.DelegatingMethodAccessorImpl.invoke(Unknown Source)
at java.lang.reflect.Method.invoke(Unknown Source)
at org.eclipse.equinox.launcher.Main.invokeFramework(Main.java:549)
at org.eclipse.equinox.launcher.Main.basicRun(Main.java:504)
at org.eclipse.equinox.launcher.Main.run(Main.java:1236)
SNAFU!

3. Let’s have
some fun!

4. Shout out
your
answer

6. Which browser does this code open?
a) Internet Explorer
b) Opera
c) FireFox
d) Safari
e) The default browser in your machine
class Google {
public static void main(String []args) {
http://www.google.com
System.out.println("Hello world");
}
}

7. int i = (false) ? 1 : null;
System.out.println(i);

8. What does this program print?
class MyThread implements Runnable {
public void run() {
System.out.println("In run method; thread name is:
" +
Thread.currentThread().getName());
}
public static void main(String args[]) throws
Exception {
Thread myThread = new Thread(new MyThread());
myThread.run();
System.out.println("In main method; thread name
is : " +
Thread.currentThread().getName());
}
}

9. Answer
In run method; thread name is: main
In main method; thread name is : main

10. What does this program print?
class CallThread extends Thread {
public void run() {
System.out.println("In CallThread.run()");
}
public static void main(String []s) {
Thread thread = new CallThread();
thread.start();
thread.start();
}
}

11. Answer
In CallThread.run()
Exception in thread "main"
java.lang.IllegalThreadStateException
at java.lang.Thread.start(Thread.java:705)
at CallThread.main(CallThread.java:9)
Never call the start() method twice on the same thread.

12. Determine the output/behaviour of this program
List<String> aList = new ArrayList<>();
aList.add("one");
aList.add("two");
aList.add("three");
Iterator listIter = aList.iterator();
while(listIter.hasNext()) {
System.out.println(listIter.next());
aList.add("four");
}

13. Answer
This program throws java.util.ConcurrentModificationException
Because the iterators of ArrayList are fail-fast; it fails by throwing
ConcurrentModificationException if it detects that the underlying
container has changed when it is iterating over the elements in the
container. This behavior is useful in concurrent contexts when one
thread modifies the underlying container when another thread is
iterating over the elements of the container.
You can use CopyOnWriteArrayList for making such changes to the
underlying container when iteration is happening.

14. What is the output of this program?
class Max {
public static void main(String []args) {
int i = ~0;
System.out.println(i);
}
}
A. This program prints the value of Integer.MAX_VALUE
B. This program prints the value of Integer.MIN_VALUE
C. This program prints “0”
D. This program prints “-1”

15. Determine the behaviour of this program:
class Bitwise {
public static void main(String []arg) {
Integer i = null;
if((i != null) & (i.intValue() != 0)) {
System.out.println(i);
}
}
}
A. This program prints 0 to the console
B. This program does not print anything output to the console and
terminates
C. This program crashes after throwing a NullPointerException
D. This program prints null to the console

16. class ReplaceAll {
public static void main(String []args) {
String date = "18-03-2017" ;
String date1 = date.replaceAll( "-" , "." ) ;
String date2 = date1.replaceAll( "." , "/" ) ;
System.out.println(date2);
}
}
What is the output of this program?
a) 18-03-2017
b) ----------
c) ……….
d) //////////

17. Supplier<String> s = () -> "hello world";
System.out.println(s.get());
What bytecode
instruction would
s.get() generate?

18. class Vehicle {
public static void run() {
System.out.println("In Vehicle.run()");
}
public static void main(String[] args) {
Vehicle vehicle = null;
vehicle.run();
}
}
class Car {
public static void run() {
System.out.println("In Car.run()");
}
}

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