Java HMTL-like Imagemap

How many of you ever wanted to use an imagemap in Java (awt - swingx)?, well all you need to do is download the code from github and you need to make an image for each element of the imagemap and put the region or element in the place that you want it to appear, It's easier if you open the whole image in photoshop or gimp, and just start to create layers for each region, and save each layer in a different file, like this:



A tooltip shows you in which region the pointer is, you just need to add a click event listener to get the id of the region that was clicked:

sqlite4java + java (singleton) example

When I heard about sqlite4java, I didn't found any working example, so here is one:
First I've made a singleton object to connect to SQLite, but also I've made a few methods to make even more easier to use sqlite4java.

import com.almworks.sqlite4java.*;
import java.io.File;
import java.util.Stack;

public class SQLiteDB {
private static final SQLiteDB INSTANCE = new SQLiteDB();
SQLiteConnection db;
SQLiteStatement st;
// Private constructor prevents instantiation from other classes
private SQLiteDB() {
try{
db = new SQLiteConnection(new File("default.ndb"));
db.open(true);
} catch (SQLiteException ex){
System.out.println("Instantiation SQLiteException: " + ex.getMessage());
}
}
public static SQLiteDB getInstance() {
return INSTANCE;
}
public boolean exec(String str){
try{
st = db.prepare(str);
st.stepThrough();
st.dispose();
return true;
} catch (SQLiteException ex){
System.out.println("Query Execution SQLiteException: " + ex.getMessage());
return false;
}
}

public boolean prepareQuery(String str){
try{
st = db.prepare(str);
} catch (SQLiteException ex){
System.out.println("Prepare Query SQLiteException: " + ex.getMessage());
return false;
}
return true;
}

public Object[] fetch(){
try{
if(!st.step()){
st.dispose();
return null;
}
else{
if(st.hasRow()) {
int columns = st.columnCount();
Stack stack = new Stack();
for(int column = 0 ; column < columns ; column++)
stack.push(st.columnValue(column));
return stack.toArray();
} else {
st.dispose();
return null;
}
}
} catch (SQLiteException ex){
System.out.println("Fetch SQLiteException: " + ex.getMessage());
}
st.dispose();
return null;
}
public void close(){
db.dispose();
}
}

Then the test class:

public class SQLiteTest {


public static void main(String[] args) {

SQLiteDB db = SQLiteDB.getInstance();


db.exec("CREATE TABLE t1 (t1key INTEGER PRIMARY KEY,data TEXT,num double,timeEnter DATE);");
db.exec("INSERT INTO t1 VALUES(1, 'This is sample data', 3, NULL);");
db.exec("INSERT INTO t1 VALUES(2, 'More sample data', 6, NULL);");
db.exec("INSERT INTO t1 VALUES(3, 'And a little more', 9, NULL);");

Object[] res;
db.prepareQuery("select * from t1");

while((res=db.fetch()) != null){
System.out.println("Results: " + res[0] + " : " + res[1] + " : " + res[2] + " : " + res[3]);
}

db.close();

}
}

Connect Java with Mysql

If you have problems with CLASSPATH java.lang.ClassNotFoundException: com.mysql.jdbc.Driver, this might work:

1.-
install the java - mysql connector:
sudo apt-get install libmysql-java

2.-
gedit ~/.bashrc

3.-
add this 2 lines at the end:

CLASSPATH=$CLASSPATH:/usr/share/java/mysql-connector-java.jar
export CLASSPATH

thats it!