Wednesday, August 17, 2011

Eclipse Link with Editor

Link with Editor allows a a file in the project explorer to be highlighted when it is the active file in the editor.

Link with Editor inactive:



Link with Editor active:


Using SWT/JFace in Eclipse













To be able to use SWT and JFace in Eclipse, a few jar files need to be included in the Build Path.














You can access the Java Build Path from the project properties.

Sunday, August 7, 2011

Measuring Python code execution time

import time

timestart = time.time()
# code to measure here
print time.time() - timestart, "seconds"

You can also try time.clock(). It is said to be more accurate.

Monday, July 11, 2011

Java String to number conversion

This entry is from http://www.devdaily.com/java/edu/qanda/pjqa00008.shtml

Two ways to convert number to String
Method 1: using String.valueOf()
String s = String.valueOf(i);
String s = String.valueOf(f); // float
String s = String.valueOf(d); // double
String s = String.valueOf(l); // long

Method 2: using toString() method of the numeric classes
String s = new Integer(i).toString(); // or Integer.toString(i)
String s = new Float(f).toString();
String s = new Double(d).toString();
String s = new Long(l).toString();

Convert String to number:
int anInt = Integer.parseInt("17");
double aDouble = Double.parseDouble("17");

NOTE: The methods above are not exhaustive. Googling will surely yield a few more ways to do conversion.

Accessing instance variable in Python

To access a Python instance variable outside the class:

class Sample:
def __init__(self, max):
self. max = max
....

sampleinstance = Sample(2)
max = sampleinstance.max

Wednesday, July 6, 2011

Java String <-> int conversion

To convert String to int:

Integer.parseInt("17");

To convert int to String:

Integer.toString(17);

Swing JComboBox usage - Getting the text of the selected item

Here is an example of a function handling an ActionPerformed event on a Combo Box.

private void onCategoryChanged(ActionEvent ae){

JComboBox cbCategory = (JComboBox)ae.getSource();
System.out.println(cbCategory.getSelectedIndex()); // Display the item index, 1st item index is 0
System.out.println((String)cbCategory.getSelectedItem()); // Display the string of the selected item

}