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Multiple Handling Exceptions in java

I need to handle a particular exception and rest of all other exception which should gives us the same logging information but the level of logging should be different ( Former should be going to log.warn and the rest of them should be going to log.error)
try {
}
catch (someexception e) {
log.warn("some message")
-----some code----
}
catch(AllotherExceptions e) {
log.error("same message as above")
-----same code as above----
}
This needs to minimalized as the message is the same but need to make the rest of the code as a common code rather than writing it couple of times

You have several ways to do so. You can, as shown in previous answers, make successive catch statements like this :
try {
// Code that potentially throws multiple exceptions
}
catch (IOException ex) {
// Manage this particular exception case
}
catch (Exception ex) {
// Manage remaining exceptions
}
This way you'll be able to manage particular cases and define a point where all the exceptions related to the following actions will be managed. By putting this try statement early in your process (main loop, heavy service call...), you'll manage many exceptions but you'll not be able to manage specific cases since you won't know which particular actions threw them. By wrapping little specific actions (accessing files, requesting...), you'll be able to make very specific management of these exceptions.
As pointed in the answers, with Java >= 7 this syntax will work :
try {
// Code that potentially throws multiple exceptions
}
catch (IOException|SQLException ex) {
// Manage these particular exceptions
}
catch (Exception ex) {
// Manage remaining exceptions
}
This way is to be used when you need to manage different exceptions the exact same way. It's particularly helpful when a single action would throw different exceptions (ie accessing files) but you only want want to manage a few specific error cases in particular and not worrying about everything that can be thrown.

You can use multiple catch blocks to accomplish this, and catch Exception, the base class for all checked exceptions, last. For example:
try {
// Your code here.
} catch (SpecificException e) {
log.warn("Warning!", e);
} catch (AnotherSpecificException e) {
log.warn("Another warning!", e);
} catch (Exception e) {
log.error("Error!", e)
}

Just add several catch sections and finish with a catch all.
try {
// Some code
}
catch (IOException ex) {
logger.log(ex);
throw ex;
catch (Exception ex) {
logger.log(ex);
throw ex;
}
Read more here: Documentation

try{
//try something
} catch (SomeTypeException e){
//things
} catch (AnotherException e){
//AnotherThings
}

The following example, which is valid in Java SE 7 and later, eliminates the duplicated code:
try{
}
catch (IOException|SQLException ex) {
logger.log(ex);
throw ex;
}

since java 7 you can do a try-Multicatch
try {
new Foo("").doSomething();
} catch (Exception1 | Exception2 e) {
e.printStackTrace();
}

Create shortcut with minimized window

Good morning, I have a Java code using JShortcut, the problem is I can not create the shortcut with the minimized window, try looking for properties as windowstyle, but find nothing.
Code.
public void createDesktopShortcut() {
try {
link.setFolder(JShellLink.getDirectory("desktop"));
link.setName("ie");
link.setPath(filePath);
//windowstyle = 7
link.save();
} catch (Exception ex) {
ex.printStackTrace();
}
}
How can I add this option?

MusicXML files in java swing - visual representation and dynamic editing

I'm developing a desktop application with java swing which should be able to display the visual content (notes, clefs, measures) defined in a MusicXML file in the frame. All .xml parsers that I found allow me to only create trees. I couldn't display the content with the JEditorPane, too.
Can I do it or will I need to first transform it dynamically to some other format such as .pdf? If so - how can I do it in java?

Use a JTextArea to let the user edit raw XML. Load the file in the background using SwingWorker, as shown here, to mitigate the effect of any latency.
#Override
protected Integer doInBackground() {
BufferedReader in = null;
try {
in = new BufferedReader(new FileReader("build.xml"));
String s;
try {
while ((s = in.readLine()) != null) {
publish(s);
}
} catch (IOException ex) {
ex.printStackTrace(System.err);
}
} catch (FileNotFoundException ex) {
ex.printStackTrace(System.err);
} finally {
try {
in.close();
} catch (IOException ex) {
ex.printStackTrace(System.err);
}
}
return status;
}
By visual representation, I meant that I needed a way to display this type of visual output.
You might look at the JMusicXML project, which has "some Java awt/swing graphics player." More resources may be found here.

How can I add a hyperlink to a JFace Dialog

How can I make a hyperlink in a JFace Dialog that when clicked opens the link in the default web browser. A full example would be useful. I know there is a org.eclipse.jface.text.hyperlink package but I can't find a suitable example.

Are you running an RCP application?
If so, then the following code will open your link in the default OS browser:
// 'parent' is assumed to be an SWT composite
Link link = new Link(parent, SWT.NONE);
String message = "This is a link to Google";
link.setText(message);
link.setSize(400, 100);
link.addSelectionListener(new SelectionAdapter(){
#Override
public void widgetSelected(SelectionEvent e) {
System.out.println("You have selected: "+e.text);
try {
// Open default external browser
PlatformUI.getWorkbench().getBrowserSupport().getExternalBrowser().openURL(new URL(e.text));
}
catch (PartInitException ex) {
// TODO Auto-generated catch block
ex.printStackTrace();
}
catch (MalformedURLException ex) {
// TODO Auto-generated catch block
ex.printStackTrace();
}
}
});
The above assumes that you do not want to scan existing text for hyperlinks but simply wish to create one programmatically. If the former is required then you'll need to use the API from JFace text packages or suchlike.

Java Applet In Web Page Does Not Respect Set Look And Feel

I am trying to set the look and feel (LAF) of a Java applet that is used via a web browser. I wish to set the system default LAF, but when loaded in a browser, the applet returns to the Metal LAF. When I run it as a stand-alone applet, the LAF is applied correctly. The only item I am showing the user is a JFileChooser. I have tried a number of methods to overcome this including:
1) Override the applet's start() method:
#Override
public void start() {
try {
UIManager.setLookAndFeel(UIManager.getSystemLookAndFeelClassName());
SwingUtilities.updateComponentTreeUI(this);
System.out.println("LOOK AND FEEL SET!");
}
catch (Exception ex) {
System.out.println(ex);
}
}
2) Set it in the static initializer of the applet class:
static {
try {
UIManager.setLookAndFeel(UIManager.getSystemLookAndFeelClassName());
System.out.println("LOOK AND FEEL SET!");
}
catch (Exception ex) {
System.out.println(ex);
}
}
3) Set it in the constructor of the applet:
public MyApplet() {
try {
UIManager.setLookAndFeel(UIManager.getSystemLookAndFeelClassName());
SwingUtilities.updateComponentTreeUI(this);
System.out.println("LOOK AND FEEL SET!");
}
catch (Exception ex) {
System.out.println(ex);
}
}
I am using Java 6, but targeting Java 5 on Windows. In every case, LOOK AND FEEL SET! gets printed to the console, so I know that it set it without throwing an exception. This happens irrespective of browser (using Firefox 3.6 and IE7). Why is it doing this and how can I get it to respect the LAF I designate?

I used this code in an applet I developed recently:
public void init() {
try {
UIManager.setLookAndFeel(UIManager.getSystemLookAndFeelClassName());
} catch (Exception ex) {
// Just accept the default L&F
}
SwingUtilities.updateComponentTreeUI(this);
super.init();
// Now add components...
}
See also Look-and-feel of an applet window changes on subsequent displays (I have not solved this problem because my applet did not need to open pop-up windows.)

So I tried finnw's answer and marked it accepted without realizing that I had also made some other modifications to my code. When I was cleaning out code I removed my mods and left finnw's, but then it was broken again.
These were the changes that had made that worked:
JFileChooser chooser = new JFileChooser();
try {
UIManager.setLookAndFeel(UIManager.getSystemLookAndFeelClassName());
SwingUtilities.updateComponentTreeUI(chooser);
}
catch (Exception ex) {
System.out.println(ex);
}
So what I ended up doing here is setting the look and feel for the file chooser outright, instead of trying to force the LAF for the whole applet. It's kind of a hack, but the file chooser is the only part of the UI that the user even sees anyway.

There does appear to be one obscure mistake that virtually every applet ever makes. Swing (also AWT components) is being used off the AWT Event Dispatch Thread (EDT). The applet threading model is a little eccentric.
This is the one time when invokeAndWait should be used with this extreme boilerplate:
#Override public void init() {
try {
java.awt.EventQueue.invokeAndWait(new Runnable() { public void run() {
initEDT();
}});
} catch (java.lang.InterruptedException exc) {
Thread.currentThread().interrupt();
} catch (java.lang.reflect.InvocationTargetException exc) {
throw new Error(exc.getCause());
}
}