Output Resultset in JTextArea

Hi,
I have encountered a problem which catch the sql exception... when i try to display my selected data in a jTextArea of another tab pane.
displayResultsQ(res);
when this method is called it goes to exception and couldnt go thru to display my result in make_mining_panel.
but the result set: res works as it print on screen for the result set when call
System.out.println("Mining select:"+ res);
does anyone know how to overcome this problem since I have been trying many times and still couldnt figure out why. the displayResultsQ(Resultset rs) method did work previously when try to put a result set and output in the MakeSearchPanel class.
thks
z
Below are the codes
Class MakeSearchPanel{
else if (s=="Display Data")
//handleQuery();
TableModel model = doSQL(jTextq1.getText());
table.setModel(model);
System.out.println("table Create");
try{
ResultSet res = executeSQLMining(jTextq1.getText());
System.out.println("Mining select:"+ res);
//try{
displayResultsQ(res);
System.out.println("display result");
// catch(Exception e){
// System.out.println("didnt go thru");}
catch(Exception e){System.out.println("didnt go thru");}
void displayResultsQ(ResultSet r) throws SQLException
ResultSetMetaData rmeta = r.getMetaData();
int numColumns=rmeta.getColumnCount();
String text="";
for(int i=1;i<=numColumns;++i)
if(i<numColumns)
text+=rmeta.getColumnName(i)+" | ";
else
text+=rmeta.getColumnName(i);
text+="\n";
while(r.next())
for(int i=1;i<=numColumns;++i)
if(i<numColumns)
text+=r.getString(i)+" | ";
else
text+=r.getString(i).trim();
text+="\n";
//m_OutText.setText(text);
make_mining_panel.m_OutText.setText(text);
//make_mining_panel is a another class extends jpanel that hold jtextarea:m_OutText
System.out.println("output to mining panel");
}

Check out the link shown below:
http://support.microsoft.com/default.aspx?scid=http://support.microsoft.com:80/support/kb/articles/Q232/5/80.ASP&NoWebContent=1
If that doesn't solve your problem, also check out the discussions at the link shown below:
http://forum.java.sun.com/thread.jsp?forum=48&thread=415887
;o)
V.V.

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rgfirefly24 wrote:
right it may be shorter and it may work. I'm not denying that fact.
and i <know> my code as it is doesnt work. But if you remove all the extra classes (output, outputPanel) and run it straight to system.out.print it does exactly what its sapposed to. Its the fact that i'm getting confused on how to send the data from the thread method run to the JTextArea. Well I can't say this any clearer I think. Take my code. Read it. Figure out why it works.
I mean you use a print stream to System.out.println and you know that works. So I created you a PrintStream that instead of outputting to the console outputs to a text area. But this isn't good enough? Why?
Especially in light of the fact that connecting the threads back to this text area is your admitted problem and I solved that. The outputstream class I wrote does exactly that.
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You feel free to point out where in this code of yours you think the text area would get updated.
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         } // End method displayResult
     * Create the GUI and show it. For thread safety,
     * this method should be invoked from the
     * event dispatch thread.
     public void createAndShowGUI( Product myProduct, OfficeSupplies myOfficeSupplies, int maxNumber )
             //Create and set up the window.
             JFrame frame = new JFrame("Products");
             frame.setDefaultCloseOperation(JFrame.EXIT_ON_CLOSE);
             //Add content to the window.
             frame.add(new Panel( myProduct, myOfficeSupplies, maxNumber ));
             //Display the window.
             frame.pack();
             frame.setVisible( true );
         } // End method createAndShowGUI
     public void displayData( Product myProduct, OfficeSupplies myOfficeSupplies, int maxNumber )
          JTextArea myTextArea = new JTextArea(); // textarea to display output
          JFrame JFrame = new JFrame( "Products" );
          // For loop to display data array in a single Window
          for ( int counter = 0; counter < maxNumber; counter++ ) // Loop for displaying each product
               myTextArea.append( packageData( myProduct, myOfficeSupplies, counter ) + "\n\n" );
               JFrame.add( myTextArea ); // add textarea to JFrame
          } // End For Loop
          JScrollPane scrollPane = new JScrollPane( myTextArea ); //Creates the JScrollPane
          JFrame.setPreferredSize(new Dimension(350, 170)); // Sets the pane size
          JFrame.add(scrollPane, BorderLayout.CENTER); // adds scrollpane to JFrame
          JFrame.setDefaultCloseOperation( JFrame.EXIT_ON_CLOSE ); // Sets program to exit on close
          JFrame.setSize( 350, 170 ); // set frame size
          JFrame.setVisible( true ); // display frame
     } // End method displayData
     public String packageData( Product myProduct, OfficeSupplies myOfficeSupplies, int counter ) // Method for formatting output
          return String.format( "%s: %d\n%s: %s\n%s: %s\n%s: %s\n%s: $%.2f\n%s: $%.2f\n%s: $%.2f\n%s: $%.2f",
          "Product Number", myOfficeSupplies.getProductNumber( counter ),
          "Product Name", myOfficeSupplies.getProductName( counter ),
          "Product Brand",myProduct.getProductBrand( counter ),
          "Number of Units in stock", myOfficeSupplies.getNumberUnits( counter ),
          "Price per Unit", myOfficeSupplies.getUnitPrice( counter ),
          "Total Value of Item in Stock is", myOfficeSupplies.getProductValue( counter ),
          "Restock charge for this product is", myProduct.restockingFee( myOfficeSupplies.getProductValue( counter ) ),
          "Total Value of Inventory plus restocking fee", myOfficeSupplies.getProductValue( counter )+
               myProduct.restockingFee( myOfficeSupplies.getProductValue( counter ) ) );
     } // end method packageData
} //End Class Panel

multarnc wrote:
My instructor has not been very forthcoming with assistance to her students leaving us to figure it out on our own.Aren't they all the same! Makes one wonder why they are called instructors. <sarcasm/>
Of course it's highly likely that enough information was imparted for any sincere, reasonably intelligent student to actually figure it out, and learn the subject in the process.
And if everything were spoonfed, how would one grade the performance of the students? Have them recite from memory
public class HelloWorld left-brace
indent public static void main left-parenthesis String left-bracket right-bracket args right-parenthesis left-brace
And everywhere that Mary went
The lamb was sure to go
db

JNI - How to use the error reporting mechanism?

I've developed a C++ DLL which is loaded from a commercial Win32 application (not written by me) as a plug-in for external calculations. On its initialization the C++ DLL launches the Java VM via the JNI invocation interface. When the DLL functions are called by the application, they forward the calls to Java objects inside the Java VM, again via JNI invocation interface.
This works well, but I have encountered a weird error.
From Java I open a JFrame containing a JTextArea as small console for debug output messages. If I turn output to this debug console off (my printToConsole routine checks whether a boolean flag is set), the string concatenation operator may lead to a crash of the Java VM.
For example, if in one of the Java functions called from the
DLL via JNI invocation interface the following is the first statement,
it leads to a crash of the Java VM and the application that loaded the C++ proxy DLL.
String test=""+Math.random(); // String test not used later
Interestingly, if I comment this statement out, the Java code works fine WITHOUT any crash. I've already thought about potential races and synchronization issues in my code, but I don't see where this is the case. And the string concatenation error fails as well, if I insert sleep() statements in front of it and at other places in the code. However, if I turn on log messages printed to my JFrame debug console (containing a JTextArea), the String concatenation works without problems.
So maybe the JNI interface has a bug and affects the Java VM; I don't see where my JNI code is wrong.
One problem is that I do not get any stdout output, as the C++ proxy DLL is loaded by the Windows application, even if I start the Windows application from the DOS command line (under Windows).
Does anyone know how to use the error reporting mechanism?
http://java.sun.com/j2se/1.4.2/docs/guide/vm/error-handling.html
Is it possible that the JVM, when it crashes, writes debug information about the crash into a file instead of stdout/stderr?
My C++ proxy DLL was compiled in debug mode, but the commercial application (which loaded the DLL) is very likely not.
I do not know hot to find the reason why the String concatenation fails inside the Java function called from the C++ DLL via JNI.

Yes, I've initially thought about errors in the C++ code too. But the C++ code is actually very simple and short. It doesn't allocate anything on the C++ side. It allocates a couple of ByteBuffers inside the Java VM however via JNI invocation interface calls of env->NewDirectByteBuffer(). The native memory regions accessed via the ByteBuffers are allocated not by my own C++ code, but by the program that calls my DLL (the program is Metastock).
The interesting thing is that everything works fine if output to my debug console is enabled, which means that in the Java print routine getConsoleLoggingState() returns true and text is appended to the jTextArea.
static synchronized void print(String str)
{ MetaStockMonitor mMon=getInstance();
if ( mMon.getFileLoggingState() && mMon.logFileWriter!=null) {
mMon.logFileWriter.print(str);
mMon.logFileWriter.flush();
if ( mMon.getConsoleLoggingState() ) {
mMon.jTextArea1.append(str);
Only if output to the JTextArea is turned off (ie. getConsoleLoggingState()==false), the crash happens when the FIRST statement in the Java routine called via JNI invocation interface is a (useless) String concatenation operation, as described above.
String test=""+Math.random(); // String test not used later
Moreover, the crash happens BEFORE the allocated ByteBuffer objects are accessed in the Java code. But again, if console output is turned on, it works stable. If console output is turned off, it works when the (useless) String concatenation operation is removed in the Java routine called from C++.
I've already thought about potential races (regarding multiple threads), but this can be ruled out in my case. It almost appears as if the JVM can have problems when called by the invocation interface (I tested it with Java 1.4.2 b28).
All the calls between C++ and Java go ALWAYS in the direction from C++ code to Java. Unfortunately, there is no special JRE version with extensive logging capabilities to facilitate debugging. And the problem is not easily reproducible either.
JNIEnv* JNI_GetEnv()
JNIEnv *env;
cached_jvm->AttachCurrentThread((void**)&env,NULL);
fprintf(logfile,"env=%i\n",env);
fflush(logfile);
return env;
// function called by Metastock's MSX plug-in interface
BOOL __stdcall createIndEngine (const MSXDataRec *a_psDataRec,
const MSXDataInfoRecArgsArray *a_psDataInfoArgs,
const MSXNumericArgsArray *a_psNumericArgs,
const MSXStringArgsArray *a_psStringArgs,
const MSXCustomArgsArray *a_psCustomArgs,
MSXResultRec *a_psResultRec)
a_psResultRec->psResultArray->iFirstValid=0;
a_psResultRec->psResultArray->iLastValid=-1;
jthrowable ex;
jmethodID mid;
JNIEnv* env=JNI_GetEnv();
jobject chart=getChart(env, a_psDataRec);
if ( chart==NULL) {
return MSX_ERROR;
jobject getChart (JNIEnv* env, const MSXDataRec *a_psDataRec)
jthrowable ex;
jmethodID mid;
int closeFirstValid, closeLastValid;
closeFirstValid=a_psDataRec->sClose.iFirstValid;
closeLastValid=a_psDataRec->sClose.iLastValid;
long firstDate, firstTime;
if (closeFirstValid>=1 && closeFirstValid<=closeLastValid) {
firstDate = a_psDataRec->psDate[closeFirstValid].lDate;
firstTime = a_psDataRec->psDate[closeFirstValid].lTime;
} else {
firstDate=0;
firstTime=0;
jclass chartFactoryClass = env->FindClass("wschwendt/metastock/msx/ChartFactory");
if (ex= env->ExceptionOccurred() ) {
env->ExceptionDescribe();
env->ExceptionClear();
sprintf(sbuf, "DLL: Cannot find class ChartFactory\n");
printSBufViaJava(sbuf);
return NULL;
mid = env->GetStaticMethodID(chartFactoryClass, "getInstance", "()Lwschwendt/metastock/msx/ChartFactory;");
if (ex= env->ExceptionOccurred() ) {
env->ExceptionDescribe();
env->ExceptionClear();
sprintf(sbuf, "DLL: Cannot find method ID for ChartFactory.getInstance()\n");
printSBufViaJava(sbuf);
return NULL;
jobject chartFactory=env->CallStaticObjectMethod(chartFactoryClass, mid);
if (ex= env->ExceptionOccurred() ) {
env->ExceptionDescribe();
env->ExceptionClear();
sprintf(sbuf, "DLL: Exception while calling ChartFactory.getInstance()");
printSBufViaJava(sbuf);
return NULL;
mid = env->GetMethodID(chartFactoryClass, "getChartID", "(Ljava/nio/ByteBuffer;Ljava/nio/ByteBuffer;Ljava/nio/ByteBuffer;Ljava/nio/ByteBuffer;IIIIIII)F");
if (ex= env->ExceptionOccurred() ) {
env->ExceptionDescribe();
env->ExceptionClear();
sprintf(sbuf, "DLL: Cannot find method ID for ChartFactory.getChartID()\n");
printSBufViaJava(sbuf);
return NULL;
jobject symbolBuf=env->NewDirectByteBuffer(a_psDataRec->pszSymbol, strlen(a_psDataRec->pszSymbol) );
if (ex= env->ExceptionOccurred() ) {
env->ExceptionDescribe();
env->ExceptionClear();
sprintf(sbuf, "DLL: Cannot allocate symbolBuf\n");
printSBufViaJava(sbuf);
return NULL;
jobject securityNameBuf=env->NewDirectByteBuffer(a_psDataRec->pszSecurityName, strlen(a_psDataRec->pszSecurityName) );
if (ex= env->ExceptionOccurred() ) {
env->ExceptionDescribe();
env->ExceptionClear();
sprintf(sbuf, "DLL: Cannot allocate securityNameBuf\n");
printSBufViaJava(sbuf);
return NULL;
jobject securityPathBuf=env->NewDirectByteBuffer(a_psDataRec->pszSecurityPath, strlen(a_psDataRec->pszSecurityPath) );
if (ex= env->ExceptionOccurred() ) {
env->ExceptionDescribe();
env->ExceptionClear();
sprintf(sbuf, "DLL: Cannot allocate securityPathBuf\n");
printSBufViaJava(sbuf);
return NULL;
jobject securityOnlineSourceBuf=env->NewDirectByteBuffer(a_psDataRec->pszOnlineSource, strlen(a_psDataRec->pszOnlineSource) );
if (ex= env->ExceptionOccurred() ) {
env->ExceptionDescribe();
env->ExceptionClear();
sprintf(sbuf, "DLL: Cannot allocate onlineSourceBuf\n");
printSBufViaJava(sbuf);
return NULL;
// Java Function call leads to crash, if console output is turned off and
// the first statement in the Java routine is a (useless) string concatenation.
// Otherwise it works stable.
jfloat chartID=env->CallFloatMethod(chartFactory, mid, securityNameBuf, symbolBuf,
securityPathBuf, securityOnlineSourceBuf, (jint)(a_psDataRec->iPeriod),
(jint)(a_psDataRec->iInterval), (jint)(a_psDataRec->iStartTime),
(jint)(a_psDataRec->iEndTime), (jint)(a_psDataRec->iSymbolType),
(jint)firstDate, (jint)firstTime );
if (ex= env->ExceptionOccurred() ) {
env->ExceptionDescribe();
env->ExceptionClear();
sprintf(sbuf, "DLL: Exception while calling ChartFactory.getChartID()");
printSBufViaJava(sbuf);
return NULL;

Copy in sand-boxed app. in 1.6.0_24+

<ul>
<li>Problem Summary
<li>Question
<li>Typical Output
<li>See Also
<li>Accumulated Results
<ul>
<li>Not grabbing focus
<li>Grabbing focus
</ul>
<li>Source
<ul>
<li>PropertyProbe.java
<li>propertyprobe.jnlp
<li>js.html
<li>Java Scripts
</ul>
<li>Post Revisions
</ul>
<h2><a name="summary"></a>Problem Summary</h2>
A security bug was fixed recently in the JRE (1.6.0_24 in Sun's JRE). The result of the fix is that sand-boxed apps. no longer provide 'Ctrl-c' copy (or cut/paste) functionality by default on text output controls like JTextArea & JTable.
While Ctrl-c copy no longer works by default, it is possible to add the functionality back in for any applet run in a 'Next Generation' Java Plug-In. Since Java Web Start existed, JWS provided sand-boxed copy via. the JNLP API's javax.jnlp.ClipboardService, & since Sun 1.6.0_10, & the next gen. plug-in, embedded applets can be deployed using JWS & can access the JNLP API.
I have redesigned an applet that relied on the old functionality, to now use the JNLP API Services if available.
<h2><a name="question"></a>Question</h2>
Does it work for you?
To answer that question:
<ol>
<li>Surf on over to the applet at http://pscode.org/prop/js.html and attempt to copy the data. See the instructions in the page for details of how to copy using the old and new forms of the applet. If the button appears, you should be prompted as to whether to allow the copy.
<li>Paste the data here (assuming the copy is successful). Or report if it fails to copy or the applet fails to appear.
</ol>
<h2><a name="egoutput"></a>Typical Output</h2>
This is what you might see at the applet.
||Property||Value||
|java.version|1.6.0_24|
|java.vendor|Sun Microsystems Inc.|
|os.name|Windows 7|
|os.version|6.1|
<h2><a name="related"></a>See Also</h2>
This relates to the thread Copy & Paste Function in Java JDK 6 Update 24. That thread contains some interesting comments, including:
<ul>
<li>A link to Sami Koivu's blog entry that explains the security bug.
<li>My Re: Copy & Paste Function in Java JDK 6 Update 24 table.
</ul>
<h2><a name="results"></a>Accumulated Results</h2>
<p>The first form of the applet showed a variety of problems with 'post copy focus', if the security prompt appeared in the JWS form of the applet.
<h3><a name="nograbfocus"></a>Not grabbing focus</h3>
||Reporter||Browser||Version||OS name||OS version||Java Vendor||Java version||Focus post dialog||Comments||
|Andrew Thompson|IE|8.0.7600.16385|Windows 7|6.1|Sun Microsystems Inc.|1.6.0_24|applet|(1)|
|Andrew Thompson|Chrome|10.0.648.151|Windows 7|6.1|Sun Microsystems Inc.|1.6.0_24|page|(2)|
|Andrew Thompson|FF|3.6.16|Windows 7|6.1|Sun Microsystems Inc.|1.6.0_24|*nothing*|(3)|
|Walter Laan|FF|3.6.16|Windows 7|6.1|Sun Microsystems Inc.|1.6.0_20|*locked*|(4)|
|almightywiz|FF|3.6.16|Windows 7|6.1|Sun Microsystems Inc.|1.6.0_24|?|(5)|
|camickr|IE|8|Windows XP|5.1|Sun Microsystems Inc.|1.6.0_07|N/A|(6)|
|Christian|FF|3.6.15|Windows XP|5.1|Sun Microsystems Inc.|1.6.0_24|no problems|(7)|
|Walter Laan|?|?|Windows XP|5.1|Sun Microsystems Inc.|1.7.0-ea|page?|(8)|
|abillconsl|FF|3.6.13|Windows XP|5.1|Sun Microsystems Inc.|1.6.0_12|?|(9)|
<ol>
<li>Makes 'Ding' sound when copying the alert is dismissed (who said MS was not security conscious?).
<li>The only way to refocus the applet in Chrome is to click in it with the mouse.
<li>'Alt space' allowed me to minimize/restore FF, but no key combo. I could think of would restore focus to controls in the browser or applet.
<li>Reported serious problems with focus for FF on 1st start-up using 1.6.0_20 JRE. Unable to reproduce on the 1.6.0_24 JRE. Ref. {message:id=9470476}, {message:id=9470587}
<li>Reported no problems with focus. Ref. {message:id=9470371}
<li>1st report for a pre plug-in2 JRE. IE 8 produced no prompts (as expected), so the 'Focus post dialog' does not apply. No auditory warnings. Ref. {message:id=9470761}
<li>'No problems with focus.'. Ref. {message:id=9474121}
<li>Focus returned to page, presumably. Ref. {message:id=9474513}
<li>Ctrl-a seemed to do nothing. No mention of focus. Ref. {message:id=9477829}
</ol>
<h3><a name="grabfocus"></a>Grabbing focus</h3>
<p>The second form of the applet has a provision to grab the focus immediately after the copy (and presumably after the trust dialog).
||Reporter||Browser||Version||OS name||OS version||Java Vendor||Java version||Focus post dialog||Comments||
|camickr|IE|8|Windows XP|5.1|Sun Microsystems Inc.|1.6.0_07|N/A|(1)|
|Andrew Thompson|IE|8.0.7600.16385|Windows 7|6.1|Sun Microsystems Inc.|1.6.0_24|applet|-|
|Andrew Thompson|Chrome|10.0.648.151|Windows 7|6.1|Sun Microsystems Inc.|1.6.0_24|applet|-|
|Andrew Thompson|FF|3.6.16|Windows 7|6.1|Sun Microsystems Inc.|1.6.0_24|applet|-|
|Paŭlo Ebermann|FF?|?|Linux2.6.34.7-0.7-desktop|2.6.34.7-0.7-desktop|Sun Microsystems Inc.|1.6.0_20|?|(2)|
|bogdana|IE|9.0.8112.16421|Windows 7 |6.1|Sun Microsystems Inc.|1.6.0_22 |applet|(3)|
<ol>
<li>The first result for camickr can be inferred from the fact that a pre plug-in2 applet should behave the same in both forms of the applet. Ref. {message:id=9470761}
<li>There are further updates on that thread that have not yet been reflected here. See the thread for details. Ref. P.E. comments at SO
<li>Also reported the auditory warning in IE when dialog disappears. Ref. {message:id=9488352}
</ol>
<h3><a name="java"></a>PropertyProbe.java</h3>
package org.pscode.tool.property;
import java.awt.*;
import java.awt.event.*;
import java.awt.datatransfer.StringSelection;
import javax.swing.*;
import javax.swing.table.*;
import javax.swing.border.EmptyBorder;
import java.util.Locale;
import java.security.AccessControlException;
import javax.jnlp.*;
/** Adds a comma delimited list of property names defined in the
props param, to the constructor of a new PropertiesPanel and
displays it. */
public class PropertyProbe extends JApplet {
    static String[] defaultProps = {
        "os.name",
        "os.version",
        "os.arch",
        "java.vendor",
        "java.version",
        "java.vm.version",
        "default_locale",
        "display_mode",
        "win.highContrast.on",
        "win.text.fontSmoothingOn",
        "win.defaultGUI.font",
        "awt.font.desktophints",
        "awt.mouse.numButtons",
        "awt.multiClickInterval"
    public void init() {
        String propertyNames = getParameter("prop");
        String[] props;
        if (propertyNames==null) {
            //getContentPane().add( new JLabel("Must specify 'prop' to query!") );
            props = defaultProps;
        } else {
            props = propertyNames.split(",");
        boolean grabFocus = getParameter("jnlp.grab.focus")!=null;
        System.out.println("jnlp.grab.focus: " + grabFocus);
        boolean jnlpServicesAvailable = getParameter("jnlp.launched")!=null;
        PropertyPanel pp = new PropertyPanel(props, jnlpServicesAvailable, grabFocus);
        pp.setPreferredSize(new Dimension(200,140));
        getContentPane().add( pp );
        validate();
    public static void main(final String[] args) {
        Runnable r = new Runnable() {
            public void run() {
                String[] props = defaultProps;
                if (args.length>0) {
                    props = args;
                boolean jnlpServicesAvailable = false;
                try {
                    Class.forName("javax.jnlp.ServiceManager");
                    jnlpServicesAvailable = true;
                    System.out.println("JNLP services available!");
                } catch(Throwable t) {
                    t.printStackTrace();
                    System.out.println("JNLP services ***NOT*** available!");
                PropertyPanel pp = new PropertyPanel(props, jnlpServicesAvailable, false);
                pp.setPreferredSize(new Dimension(200,200));
                JPanel mainPanel = new JPanel(new BorderLayout());
                mainPanel.setPreferredSize(new Dimension(400,200));
                mainPanel.add( pp );
                JFrame f = new JFrame("Property Probe");
                f.setDefaultCloseOperation(JFrame.EXIT_ON_CLOSE);
                f.setContentPane(mainPanel);
                f.pack();
                try {
                    f.setLocation(50,50);
                    f.setLocationRelativeTo(null);
                    f.setLocationByPlatform(true);
                    f.setMinimumSize( f.getSize() );
                } catch(Exception e) {
                f.setVisible(true);
        EventQueue.invokeLater(r);
class PropertyPanel extends JPanel {
    /** The JNLP API service used for copy in apps. deployed using JWS. */
    private ClipboardService clipboardService;
    private boolean grabFocus = false;
    private JTable table;
    /** A widget (JTable) of values for properties specified in the
    array of property names. The properties are sourced from the
    system, environment and AWT toolkit properties.If there is no
    value defined in one of those three, 'null' is displayed. */
    PropertyPanel(String[] props, boolean jnlpServicesAvailable, boolean grabFocus) {
        super(new BorderLayout());
        this.grabFocus = grabFocus;
        setBorder( new EmptyBorder(5,5,5,5) );
        String[][] propValuePairs = new String[props.length][2];
        for ( int ii=0; ii<props.length; ii++ ) {
            propValuePairs[ii][0] = props[ii];
            propValuePairs[ii][1] = getProperty( props[ii] );
        String[] header = {"Property","Value"};
        table = new JTable( propValuePairs, header );
        try {
            table.setAutoCreateRowSorter(true);
        } catch (Exception e) {
            // pre 1.6 JRE, go with an unsorted table
        this.add( new JScrollPane( table ) );
        if (jnlpServicesAvailable) {
            try {
                clipboardService =
                    (ClipboardService)ServiceManager.
                        lookup("javax.jnlp.ClipboardService");
                Action action = new CopyAction(
                    "Copy",
                    null,
                    "Copy data",
                    new Integer(KeyEvent.VK_CONTROL+KeyEvent.VK_C));
                table.getActionMap().put( "copy", action );;
                final JButton copy = new JButton("Copy to clipboard");
                copy.setMnemonic('c');
                copy.addActionListener( action );
                JPanel bottomPanel = new JPanel(new FlowLayout(FlowLayout.CENTER));
                bottomPanel.add(copy);
                add(bottomPanel, BorderLayout.SOUTH);
            // Expecting only javax.jnlp.UnavailableServiceException. But if we
            // try to catch it, we get a NoClassDefFoundError in non JWS apps.!
            } catch(Throwable use) {
                use.printStackTrace();
                System.err.println("Copy services not available. Copy using 'Ctrl-c'.");
    /** Check for properties in the order of the toolkit, system
    then environment, on the basis that all the toolkit properties
    are    available to sandboxed apps., as well as some of the system
    properties, but none of the environment properties. */
    public String getProperty(String prop) {
        String value = null;
        if ( prop.equals("default_locale") ) {
            return Locale.getDefault().toString();
        if ( prop.equals("display_mode") ) {
            return getDisplayModeString();
        value = getDesktopProperty(prop);
        if (value!=null) {
            return value;
        value = getSystemProperty(prop);
        if (value!=null) {
            return value;
        value = getEnvironmentProperty(prop);
        if (value!=null) {
            return value;
        return "null";
    public String getSystemProperty( String prop ) {
        try {
            return System.getProperty( prop );
        } catch(AccessControlException ace) {
            // this property is either restricted, /or/ 'null'
            // the plug-in will not reveal which, for a sandboxed
            // app.
            return "unknown";
    public String getEnvironmentProperty(String prop) {
        try {
            Object value = System.getenv().get(prop);
            if (value==null) {
                return null;
            } else {
                return value.toString();
        } catch(AccessControlException ace) {
            return null;
    public String getDesktopProperty(String prop) {
        Object value = Toolkit.
            getDefaultToolkit().
            getDesktopProperty(prop);
        if (value==null) {
            return null;
        } else {
            return value.toString();
    public String getDisplayModeString() {
        DisplayMode dm = GraphicsEnvironment.
            getLocalGraphicsEnvironment().
            getDefaultScreenDevice().
            getDisplayMode();
        String value =
            dm.getWidth()
            +
            "x"
            +
            dm.getHeight()
            +
            +
            dm.getRefreshRate()
            +
            "Hz "
            +
            dm.getBitDepth()
            +
            "bit"
        return value;
    public void copyData(Component source) {
        TableModel model = table.getModel();
        StringBuilder sb = null;
        if (true) {
            sb = new StringBuilder();
            for (int ii=0; ii<model.getRowCount(); ii++) {
                for (int jj=0; jj<model.getColumnCount(); jj++) {
                    sb.append( model.getValueAt(ii,jj).toString() );
                    sb.append( "\t" );
                sb.append( "\n" );
        String s = sb.toString();
        if (s==null || s.trim().length()==0) {
            JOptionPane.showMessageDialog(this,
                "There is no data in the table!");
        } else {
            StringSelection selection =
                new StringSelection(s);
            clipboardService.setContents( selection );
        if (grabFocus) {
            source.requestFocus();
    class CopyAction extends AbstractAction {
        public CopyAction(String text, ImageIcon icon,
            String desc, Integer mnemonic) {
            super(text, icon);
            putValue(SHORT_DESCRIPTION, desc);
            putValue(MNEMONIC_KEY, mnemonic);
        public void actionPerformed(ActionEvent e) {
            copyData((Component)e.getSource());
}<h3><a name="jnlp"></a>propertyprobe.jnlp</h3>
<?xml version='1.0' encoding='UTF-8' ?>
<jnlp spec='1.0'
    href='propertyprobe.jnlp'>
    <information>
        <title>Property Probe</title>
        <vendor>PSCode.org - Andrew Thompson</vendor>
        <description kind='one-line'>
            Table for common Java properties.
        </description>
        <shortcut online='false'>
            <desktop/>
        </shortcut>
    </information>
    <resources>
        <j2se version='1.2+' />
        <jar href='propprobe.jar' main='true' />
    </resources>
    <applet-desc
        main-class='org.pscode.tool.property.PropertyProbe'
        name='applet'
        width='600'
        height='300' >
        <param name='jnlp.launched' value='true' />
    </applet-desc>
</jnlp><h3><a name="html"></a>js.html</h3>
<!DOCTYPE HTML PUBLIC "-//W3C//DTD HTML 4.01 Transitional//EN">
<HTML>
<HEAD>
<title>
Property Probe - applet
</title>
<script type='text/javascript' src="http://www.java.com/js/deployJava.js"></script>
<script type='text/javascript' src='http://pscode.org/file/urlcode.js'></script>
<script type='text/javascript' src='http://pscode.org/file/queryprm.js'></script>
<script type='text/javascript' src='http://pscode.org/file/urlquery.js'></script>
<script type='text/javascript' src='http://pscode.org/file/appletparams.js'></script>
<script type='text/javascript'>
archiveName = "";
if (true) {
    archiveName = 'propprobe.jar';
} else {
    archiveName = 'propprobe-trusted.jar';
var attributes = {
    code:'org.pscode.tool.property.PropertyProbe',
    codebase:'../lib',
    archive:archiveName,
    width:'600',
    height:'400'
var version = '1.2';
var params;
params.jnlp_href='../lib/propertyprobe.jnlp';
</script>
</HEAD>
<BODY>
<H1>Property Probe</H1>
<script type='text/javascript'>
deployJava.runApplet( attributes, params, version );
</script>
<P>.. (text & instructions)
</BODY>
</HTML><h3><a name="scripts"></a>JavaScripts linked in the HTML</h3>
'Sold separately' - pull them by direct fetch into your browser window, if you're that interested.
<h2><a name="revisions"></a>Post Revisions</h2>
Edited by: Andrew Thompson on Mar 26, 2011 5:32 AM
Changed subject.
Edited by: Andrew Thompson on Mar 26, 2011 5:19 PM
Added accumulated results and index, other tweaks.
Edited by: Andrew Thompson on Mar 31, 2011 11:08 AM
Removed 'how output appears in code tags'. Added latest results, 'grab focus' results. Changed URL to invoke 'grab focus'.
Edited by: Andrew Thompson on Apr 2, 2011 4:20 AM
Added 1st result from SO - on Linux system.
Edited by: Andrew Thompson on Apr 2, 2011 6:15 AM
Added latest result.

Walter Laan wrote:
almightywiz wrote:
Walter Laan wrote:
The security popup really messes with the focus in Firefox (3.6.16) though.Not saying you're wrong, but I'm using FireFox 3.6.16, as well, and I have none of the focus troubles you've described.Cannot reproduce it now either. Weird.I got the impression you were referring to keyboard focus, so I did some further tests on focus behavior. The test results are listed in the Accumulated Results table on the 1st post.
The only browser so far that works as I'd expect, or at least as I'd like, is IE.
Applets and keyboard navigation have always been a PITA. Some time ago I vaguely recall seeing an update involving a new parameter to regulate initial focus (applet or page, ..or another applet), but for the life of me I cannot locate it now. Given that it was a parameter for initial focus, I doubt it would help in this case.
Edited by: Andrew Thompson on Mar 26, 2011 6:18 PM
Removed table which has now been expanded & added to 1st post.

How do I compare these text files (aka spell check)

I'm having the hardest time figuring out how to get this spell check to work. Basically, I need to open the dictionary.txt file and then another file which will be spell checked. Ignoring case sensitivity, punctuation, and word endings (such as ly, ing, s). And then output to the user the words that were not found in the dictionary. Here is what I have so far (and it is very basic.... there is no attempt to compare yet since I don't know how to approach this). I only have it outputting to a JTextArea what is opened minus punctuation and upper case....
import java.util.Scanner;
import java.io.*;
import java.awt.*;
import java.awt.event.*;
import javax.swing.*;
// Created Sept 4, 2004
*   @version 1.0
*   This program will store dictionary.txt to a String array and
*   open another text file to be specified by the user of the program.
*   As the scanner proceeds through the document, it will spell check
*   and output any (case insensitive) words not found in the
*   dictionary.txt file.
public class Spell extends JFrame {
    /** Area to place the individual words in the file */
    JTextArea outputDictionary, outputWord;
* Constructor for the class. Sets up the swing components.
* Prompts the user for the files to be processed. Then invokes
* the process method to actually do the work.
public Spell() {
     // A JTextArea is used to display each word found in the file.
     outputDictionary=new JTextArea("Dictionary List\n\n");
     add (new JScrollPane(outputDictionary));
     //Set the size to 300 wide by 600 pixels high
     setSize(300,600);
     setVisible(true);
        outputWord=new JTextArea("Opened Document\n\n");
        add (new JScrollPane(outputWord));
        setSize(300,600);
        setVisible(true);
    //Prompts user for the dictionary.txt file
    JFileChooser dictionary = new JFileChooser();
    int returnVal = dictionary.showOpenDialog(this);
     if (returnVal == JFileChooser.APPROVE_OPTION) {
          storeDictionary(dictionary.getSelectedFile());
    //Prompt user to open file to be checked
    JFileChooser word = new JFileChooser();
    int returnVal2 = word.showOpenDialog(this);
        if (returnVal2 == JFileChooser.APPROVE_OPTION){
            storeOpenFile(word.getSelectedFile());
public void storeDictionary(File dictionaryFile) {
     String dictionary="";
     Scanner scanner=null;
    try {
        // Delimiters specifiy where to parse tokens in a scanner
       scanner = new Scanner(dictionaryFile).useDelimiter("\\s*[\\p{Punct}*\\s+]\\s*");
    catch (FileNotFoundException fnfe) {
        JOptionPane.showMessageDialog(this,"Could not open the file");
       System.exit(-1);
     while (scanner.hasNext()) {
          dictionary=scanner.next();
          if (!dictionary.equals(""))
             outputDictionary.append(dictionary.toLowerCase()+"\n");
        System.out.println("Thank you, your dictionary is stored.");
public void storeOpenFile(File openFile){
    String word="";
    Scanner scanner2 = null;
    try {
        // Delimiters specifiy where to parse tokens in a scanner
       scanner2 = new Scanner(openFile).useDelimiter("\\s*[\\p{Punct}*\\s+]\\s*");
    catch (FileNotFoundException fnfe) {
        JOptionPane.showMessageDialog(this,"Could not open the file");
       System.exit(-1);
    //stores the words in the opened text file in a String array
     while (scanner2.hasNext()) {
          word=scanner2.next();
             if(!word.equals(""))
                    outputWord.append(word.toLowerCase()+"\n");
    System.out.println("Thanks, your file has successfully been opened.");
public static void main(String args[]) {
   Spell spellck = new Spell();
   spellck.setDefaultCloseOperation(JFrame.EXIT_ON_CLOSE);
}

Yes, he actually recommends us to use java 1.5. I have revised my code to read into a TreeSet from the dictionary.txt, but I keep getting the following error when I compile:
Note: C:\Jwork\spell1.java uses unchecked or unsafe operations.
Note: Recompile with -Xlint:unchecked for details.
Finished spell1.
Also, when I execute, nothing happens. It looks like it is going to try to do something, but the "open" dialog box never opens and no errors pop up. It just sits there executing. Any suggestions??
here is the code:
import java.util.*;
import java.io.*;
import java.awt.*;
import java.awt.event.*;
import javax.swing.*;
// Created Sept 4, 2004
*   @version 1.0
*   This program will store dictionary.txt to a String array and
*   open another text file to be specified by the user of the program.
*   As the scanner proceeds through the document, it will spell check
*   and output any (case insensitive) words not found in the
*   dictionary.txt file.
public class spell1 extends JFrame{
    JTextArea output = new JTextArea(500,500);
    Set dict = new TreeSet();
    Set file = new HashSet();
    public spell1(){
    Set dict = new TreeSet();
    Set file = new HashSet();
    //Prompts user for the dictionary.txt file
    JFileChooser dictionary = new JFileChooser();
    JFileChooser wordFiles = new JFileChooser();
    int returnVal = dictionary.showOpenDialog(this);
     if (returnVal == JFileChooser.APPROVE_OPTION) {
     storeDictionary(dictionary.getSelectedFile());
    int returnVal2 = wordFiles.showOpenDialog(this);
        if (returnVal2 == JFileChooser.APPROVE_OPTION){
            storeFile(wordFiles.getSelectedFile());
    public void storeDictionary(File dictionaryFile){
        String dictionary="";
     Scanner scanner=null;
    try {
       // Delimiters specifiy where to parse tokens in a scanner
       scanner = new Scanner(dictionaryFile).useDelimiter("\\s*[\\p{Punct}*\\s+]\\s*");
    catch (FileNotFoundException fnfe) {
        JOptionPane.showMessageDialog(this,"Could not open the file");
       System.exit(-1);
     while (scanner.hasNext()) {
          if (!dictionary.equals(""))
             dict.add(scanner.next());
        System.out.println("Thank you, your dictionary is stored.");
    public void storeFile(File wordFile){
        String word="";
        Scanner scanner2=null;
    try{
        scanner2 = new Scanner(wordFile).useDelimiter("\\s*[\\p{Punct}*\\s+]\\s*");
    catch (FileNotFoundException fnfe){
        JOptionPane.showMessageDialog(this,"Could not open the file");
        System.exit(-1);
        while(scanner2.hasNext()){
            if(!word.equals(""))
                file.add(scanner2.next());
    public static void main(String args[]){
        spell1 spellck = new spell1();
        spellck.setDefaultCloseOperation(JFrame.EXIT_ON_CLOSE);
}

Output Resultset in JTextArea

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