I am using this code to find the MAC address of a machine.This code prints directly the MAC address, but i want to return it as a string.I am completely confused.
please help.
try {
InetAddress add = InetAddress.getByName("10.123.96.102");
NetworkInterface ni1 = NetworkInterface.getByInetAddress(add);
if (ni1 != null) {
byte[] mac1 = ni1.getHardwareAddress();
if (mac1 != null) {
for (int k = 0; k < mac1.length; k++) {
System.out.format("%02X%s", mac1[k], (k < mac1.length - 1) ? "-" : "");
}
} else {
System.out.println("Address doesn't exist ");
}
System.out.println();
} else {
System.out.println("address is not found.");
}
} catch (UnknownHostException e) {
e.printStackTrace();
} catch (SocketException e) {
e.printStackTrace();
}
about = new JMenuItem("About");
about.setAccelerator(KeyStroke.getKeyStroke(KeyEvent.VK_A((Toolkit.getDefaultToolkit().getMenuShortcutMask()))));
JMenu help = new JMenu("Help");
help.add(about);
I was wondering why my aaccelerators were not working. I am running this in snow leopard with JavaSe-1.6 VM. They do work if I pull the menu down then try the key sequence. Thanks
Please explain the output of the below code:
If I call th1.run() ,the output is
EXTENDS RUN
RUNNABLE RUN
If I call th1.start() , the output is :
RUNNABLE RUN
EXTENDS RUN
Why this inconsistency . Please explain.
class ThreadExample extends Thread{
public void run(){
System.out.println("EXTENDS RUN");
}
}
class ThreadExampleRunnable implements Runnable {
public void run(){
System.out.println("RUNNABLE RUN ");
}
}
class ThreadExampleMain{
public static void main(String[] args){
ThreadExample th1 = new ThreadExample();
//th1.start();
th1.run();
ThreadExampleRunnable th2 = new ThreadExampleRunnable();
th2.run();
}
}
Hello
I have this configuration for ehCache:
<ehcache>
<defaultCache
name="defaut"
maxElementsInMemory="5"
eternal="false"
timeToIdleSeconds="20"
timeToLiveSeconds="20"
overflowToDisk="false"
diskPersistent="false"
memoryStoreEvictionPolicy="LRU"
/>
</ehcache>
How can I get access to default cache of EhCache?
CacheManager.getInstance().getCache("default") - returns null
thank you
I want to create a program for generating the series for the given base-n. ,
for example if my input is 2,then series shuould be, 00,01,10,11,etc.,(binary)
if my input is 10,then series shuould be,1,2,3,4,5,etc.,(decimal)
is there any general mechanism to find these numbers so that I can program for base-n.,
I know that when creating buttons, like next and previous, that the code can be somewhat long to get those buttons to function.
My professor gave us this example to create the next button:
private void jbtnNext_Click() {
JOptionPane.showMessageDialog(null, "Next" ,"Button Pressed",
JOptionPane.INFORMATION_MESSAGE);
try {
if (rset.next()) {
fillTextFields(false);
}else{
//Display result in a dialog box
JOptionPane.showMessageDialog(null, "Not found");
}
}
catch (SQLException ex) {
ex.printStackTrace();
}
}
Though, I do not really understand how that short and simple if statement is what makes the next button function. I see that the fillTextFields(false) uses a boolean value and that you need to initialize that boolean value in the beginning of the code I believe. I had put private fillTextFields boolean = false; but this does not seem to be right...
I'm just hoping someone could explain it better. Thanks :)
Hi, what is the best practice or best way of passing form parameters from page to page in a flow? If I have a flow where a user enters data in a form and hits next and repeats this process until they get to an approval page, what ways could I approach this problem to make the retention of data as simple as possible over the flow?
I guess you could put all the information as you go in the session but could you get into memory issues if a lot of people are using your app and going through the flow at the same time?
I absolutely love good defender games (e.g. Gemcraft, Protector: reclaiming the throne) as they can be intellectually quite challenging; it's like playing chess but a little less thinking a bit more action. Sadly, there are not that many good ones out there and I thought I would create one myself and share it with the rest of the world by making it available on-line.
I have never worked with ActionScript but when it comes to on-line games, this is the main choice. I have tried to find a decent 2D game in the form of a Java applet but to no avail. Why is this so? I could write the game, most comfortably, in Delphi for Win32 but then people would need to download the executable, which could deter some form downloading it, and also it would only work on Windows. I am also familiar with Java, having worked with Java for the last four years or so. Although I don't have much experience with games programming.
Should I note be deterred by the fact that all online games are written for in Flash and create my defender game as a Java applet, or should I consider learning ActionScript and games development for the ActionScript Virtual Machine (AS3 looks very much like Java... but still, it's an entirely new technology to me and I might never use it professionally.)
Could you, please, just answer the the question in the title? Why Flash, not Java applets? Is it only 'politics'?
public class b {
public static void main(String[] args) {
byte b = 1;
long l = 127;
// b = b + l; // 1 if I try this then it does not compile
b += l; // 2 if I try this then it does compile
System.out.println(b);
}
}
I am using this code but I have problem:
I don't understand why b=b+l; is not compiling but if I write b+=l; then it compiles and runs.
Please explain why this happens.
type first integer , type second integer, , program repeatedly outputs the second value of the number of times indicated by the first value. Example use inputs 4 and 2, 222 2 displayed. another example user inputs 3 and 8 , 88 8 displayed
hi everyone,
I work on inheritence with GUI (graphical user interfaces)
let me explain for example I made super class which is vehicle and the subclass is car, so the code to make inheritence will be
public class Car extends Vehicle
then I want to build the class Car as JFrame like
public class Car JFrame implements ActionListener {
so the problem is that I couldn't put both codes in the same class, and I need to do that.
anyone help me. thanks in advance
I wish that the question would be clear
Ok, so I'm tyring to iterate through an ArrayList and remove a specefic element. However, I am having some trouble using the For-Each like structure. When I run the following code:
ArrayList<String> arr = new ArrayList<String>();
//... fill with some values (doesn't really matter)
for(String t : arr)
{
t = " some other value "; //hoping this would change the actual array
}
for(String t : arr)
{
System.out.println(t); //however, I still get the same array here
}
My question in, how can I make 't' a pointer to 'arr' so that I am able to change the values in a for-each loop? I know I could loop through the ArrayList using a different structure, but this one looks so clean and readable, it would just be nice to be able to make 't' a pointer.
All comments are appreciated! Even if you say I should just suck it up and use a different construct.
Hi guys,
I'm working on rotating a loaded image. I set the graphics on a JPanel and then use standard AffineTransform in order to rotate it, say, 45 degrees.
Unfortunately, the image is being cut, if it exceeds the panel area.
How may I force JPanel to add scrolls to itself (while loading an image file, I would like to adjust the size of JPanel by adding the scrolls, without adjusting the size of JFrame).
Or, in other words, how to correctly rotate the whole image?
Thank you in advance for the reply!
Im a bit unsure and have to get advice.
I have the:
public class MyApp extends JFrame{
And from there i do;
MyServer = new MyServer (this);
MyServer.execute();
MyServer is a:
public class MyServer extends SwingWorker<String, Object> {
MyServer is doing listen_socket.accept() in the doInBackground()
and on connection it create a new
class Connection implements Runnable {
I have the belove DbHelper that are a singleton.
It holds an Sqlite connected. Im initiating it in the above MyApp
and passing references all the way in to my runnable:
class Connection implements Runnable {
My question is what will happen if there are two simultaneous read or `write?
My thought here was the all methods in the singleton are synchronized and
would put all calls in the queue waiting to get a lock on the synchronized method.
Will this work or what can i change?
public final class DbHelper {
private boolean initalized = false;
private String HomePath = "";
private File DBFile;
private static final String SYSTEM_TABLE = "systemtable";
Connection con = null;
private Statement stmt;
private static final ContentProviderHelper instance = new ContentProviderHelper ();
public static ContentProviderHelper getInstance() {
return instance;
}
private DbHelper () {
if (!initalized)
{
initDB();
initalized = true;
}
}
private void initDB()
{
DBFile = locateDBFile();
try {
Class.forName("org.sqlite.JDBC");
// create a database connection
con = DriverManager.getConnection("jdbc:sqlite:J:/workspace/workComputer/user_ptpp");
} catch (SQLException e) {
e.printStackTrace();
} catch (ClassNotFoundException e) {
e.printStackTrace();
}
}
private File locateDBFile()
{
File f = null;
try{
HomePath = System.getProperty("user.dir");
System.out.println("HomePath: " + HomePath);
f = new File(HomePath + "/user_ptpp");
if (f.canRead())
return f;
else
{
boolean success = f.createNewFile();
if (success) {
System.out.println("File did not exist and was created " + HomePath);
// File did not exist and was created
} else {
System.out.println("File already exists " + HomePath);
// File already exists
}
}
} catch (IOException e) {
System.out.println("Maybe try a new directory. " + HomePath);
//Maybe try a new directory.
}
return f;
}
public String getHomePath()
{
return HomePath;
}
private synchronized String getDate(){
SimpleDateFormat dateFormat = new SimpleDateFormat("yyyy-MM-dd HH:mm:ss");
Date date = new Date();
return dateFormat.format(date);
}
public synchronized String getSelectedSystemTableColumn( String column) {
String query = "select "+ column + " from " + SYSTEM_TABLE ;
try {
stmt = con.createStatement(ResultSet.TYPE_FORWARD_ONLY, ResultSet.CONCUR_READ_ONLY);
ResultSet rs = stmt.executeQuery(query);
while (rs.next()) {
String value = rs.getString(column);
if(value == null || value == "")
return "";
else
return value;
}
} catch (SQLException e ) {
e.printStackTrace();
return "";
} finally {
}
return "";
}
}
This should be simple, but I have tried if statements checking for null values and also ones checking the .length of it:
EditText marketValLow = (EditText) findViewById(R.id.marketValLow);
EditText marketValHigh = (EditText) findViewById(R.id.marketValHigh);
if (marketValLow.getText().length() != 0 && marketValHigh.getText().length() != 0) {
Intent intent = new Intent();
intent.setClass(v.getContext(), CurrentlyOwe.class);
startActivity(intent);
} else {
Toast.makeText(CurrentMarketValue.this, "You need to enter a high AND low.", Toast.LENGTH_SHORT);
}
But it doesn't detect nothing was entered. Any ideas?
Thanks!
I have a strange problem I've come across. My app can write a simple textfile to SD card and sometimes it works for some people but not for others and I have no idea why. Some people it force closes if they put some characters like "..." in it and such. I cannot seem to reproduce it as I've had no troubles but this is the code that handles it. Can anyone think of something that may lead to problems or a better to way to do it?
public void generateNoteOnSD(String sFileName, String sBody){
try
{
File root = new File(Environment.getExternalStorageDirectory(), "Notes");
if (!root.exists()) {
root.mkdirs();
}
File gpxfile = new File(root, sFileName);
FileWriter writer = new FileWriter(gpxfile);
writer.append(sBody);
writer.flush();
writer.close();
Toast.makeText(this, "Saved", Toast.LENGTH_SHORT).show();
}
catch(IOException e)
{
e.printStackTrace();
importError = e.getMessage();
iError();
}
}
Hi guys,
I have a Spring application that I believe has some bottlenecks, so I'd like to run it with a profiler to measure what functions take how much time. Any recommendations to how I should do that?
I'm running STS, the project is a maven project, and I'm running Spring 3.0.1
Cheers
Nik
This is a weird problem. Here is my code
String reply = listen.executeUrl("http://localhost:8080/JavaBridge/reply.php);
executeUrl returns as String object whatever is returned by the reply.php file.
Now comes the problem. In reply.php I am returning an PHP array and reply is a String.
When I do
System.out.println("Reply = "+reply);
I get
Reply = array(2) { [0]=> string(14) "Dushyant Arora" [1]=> string(19
) "@dushyantarora13 hi"}
But reply is still a String. How do I convert it into a String array or an Array.
If I have a try/catch block with returns inside it, will the finally block be called?
For example:
try {
something();
return success;
}
catch (Exception e) {
return failure;
}
finally {
System.out.println "i don't know if this will get printed out."
}
I know I can just type this in an see what happens (which is what I'm about to do, actually) but when I googled for answers nothing came up, so I figured I'd throw this up as a question.
Thanks!
i have the following class:
public class NewGameContract {
public boolean HomeNewGame = false;
public boolean AwayNewGame = false;
public boolean GameContract(){
if (HomeNewGame && AwayNewGame){
return true;
} else {
return false;
}
}
}
when i try to use it like so:
if (networkConnection){
connect4GameModel.newGameContract.HomeNewGame = true;
boolean status = connect4GameModel.newGameContract.GameContract();
switch (status){
case true:
break;
case false:
break;
}
return;
}
i am getting the error: incompatible types found: boolean required: int on the following switch (status) code.
what am i doing wrong please?