Which Swing component methods are thread safe?

Question

According to Swing tutorial:

Some Swing component methods are labelled \"thread safe\" in the API specification; these can be safely invoked from any

Answer 1

But you already have the answer: only those methods which are specifically documented as being thread-safe in the method JavaDoc, are threadsafe! this is from JTextComponent.setText

 * This method is thread safe, although most Swing methods
 * are not. Please see 
 * <A HREF="http://java.sun.com/docs/books/tutorial/uiswing/misc/threads.html">How
 * to Use Threads</A> for more information.     

If the method documentation doesn't say it's safe, then it isn't safe: access to the JavaDoc is therefore critical when coding against Swing

Answer 2

In Java 7, previously thread safe methods of the view components rooted in JTextComponent are no longer thread safe. A typical workaround using EventQueue.invokeLater() is shown here. The remaining model-related methods, listed here, remain thread safe.

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• JTextComponent
  • replaceSelection()
  • setText()
  • print()
  • getPrintable()

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• JTextPane
  • replaceSelection()
  • insertComponent()
  • insertIcon()
  • setLogicalStyle()
  • setCharacterAttributes()
  • setParagraphAttributes()

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• JTextArea
  • insert()
  • append()
  • replaceRange()

Answer 3

Google taught me that at least those are threadsafe. Here's an overview for the case that the link get broken again:

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• JTextPane
  • replaceSelection()
  • insertComponent()
  • insertIcon()
  • setLogicalStyle()
  • setCharacterAttributes()
  • setParagraphAttributes()

---

• JTextArea
  • insert()
  • append()
  • replaceRange()

---

• JTextComponent
  • replaceSelection()
  • setText()
  • print()
  • getPrintable()

---

• UndoManager
  • All methods.

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• DefaultStyledDocument
  • insert()
  • setLogicalStyle()
  • setCharacterAttributes()
  • setParagraphAttributes()

---

• StyleContext
  • addAttribute()
  • addAttributes()
  • removeAttribute()
  • removeAttributes()
  • reclaim()

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• AbstractDocument
  • render()
  • remove()
  • insertString()
  • createPosition()

---

• PlainDocument
  • insertString()

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• HTMLDocument
  • setParagraphAttributes()

Answer 4

For a list of classes with the comment in the javadocs & src files "is thread safe" returns the following

JEditorPane
JTextArea
AbstractDocument
DefaultCaret
DefaultStyledDocument
JTextComponent    
PlainDocument
StyleContext    
HTMLDocument
UndoManager

This is not saying that there are others documented or undocumented within the src that are thread safe.

It strikes me as a rather strange question but I would treat most components as not being threadsafe and since Swing is a single threaded model and all updates need to happen on the event dispatcher thread this is pretty easy to do.

Answer 5

But what are these Swing component methods that are labelled "thread safe"?

Most Swing components' methods are NOT thread safe. But some are. To find out which ones, you have no option but to peruse the javadocs for your target components. A carefully constructed google search might quicken the process.

Are there actually any?

Yes there are indeed. Generally speaking, if you are working with Swing components, it is likely that you are going to have to invoke both thread-safe and non-thread-safe methods. Since most methods are non-thread-safe, I prefer to err on the side of caution, and perform all actions on them in a thread-safe manner anyway.

HTH

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Not exhaustive list.

DefaultStyledDocument:

• protected void insert(int offset, DefaultStyledDocument.ElementSpec[] data) throws BadLocationException
• public void setLogicalStyle(int pos, Style s)
• public void setCharacterAttributes(int offset, int length, AttributeSet s, boolean replace)
• public void setParagraphAttributes(int offset, int length, AttributeSet s, boolean replace)

javax.swing.text.AbstractDocument:

• public void render(Runnable r)
• public void remove(int offs, int len) throws BadLocationException
• public void insertString(int offs, String str, AttributeSet a) throws BadLocationException
• public Position createPosition(int offs) throws BadLocationException

javax.swing.undo.UndoManager:
Class is threadsafe