Funny Java

2010-07-21T18:15:00.000+03:00

Consider the following code snippet:

public class SomeClass {

 @SuppressWarnings("unused")

 private Validator validator;

...

Variable validator really isn't use. It could be simply removed, by author decided to mark it as @SuppressWarnings("unused") - just in order to make compiler and Eclipse silent.

Stupid!

Collection setter

2010-04-22T18:04:00.000+03:00

There is two major ways to write setters for collection-type members.
This example combines both of them.

public void setPhones(List<PhoneNumber> phones) throws Exception
{
    this.phones = phones;
    this.phones.clear();
    this.phones.addAll(phones);
}

Compare float numbers

2010-03-04T16:14:00.000+02:00

This is how Chuck Norris compares float numbers:

if (!Float.valueOf("0.0").equals(price.getActualPrice()))
{
 return true;
}

2010-02-22T13:44:00.000+02:00

As to me, this is a really unobvious way to parse strings:


protected void parseSummaryLines()
{
    ...

    // NOTE: First letters are ommited in order to 
    // support capitalized words as well
    String RESULT_GOOD_TEXT_1 = "othing";    // Nothing
    String RESULT_GOOD_TEXT_2 = "uccessful"; // Successful
    String RESULT_BAD_TEXT_1 = "assword";    // Password
    String RESULT_BAD_TEXT_2 = "failed";     // Failed

    ...
}

Next generation programming style

2010-01-07T17:38:00.000+02:00

A very good article about programming:
http://codemonkeyism.com/generation-java-programming-style/

in particular, this one is great:
http://codemonkeyism.com/never-never-never-use-string-in-java-or-at-least-less-often/

Bad books samples

2010-01-07T17:34:00.000+02:00

Today I read a blog entry How Programming Books Promote Code Smells.

This is true: many books contain examples of bad code.

One of my favorite examples is the main method with try/catch like this one.


public static void main(String args[]) {
  try{
    FileInputStream fstream = ...
  }catch (Exception e){//Catch exception if any
    System.err.println("Error: " + e.getMessage());
  }
}

This try/catch is absolutely NOT NEEDED! If you skip them, the JVM does exactly the same work. the well-known "Throw early catch late" principle says that you shoudn't catch exception until you know what to do with it (except the trivial actions that the system does by default).

nStartFrom - 12

2009-04-01T11:47:00.000+03:00

Quite a fun usage of variable nStartFrom:


public void setStatementFromAddress(CCallableStatement ccstmt, 
    CAddressStruct address, int nStartFrom) throws SQLException
{
    nStartFrom = nStartFrom - 12; 
    ccstmt.setString(nStartFrom + 0, address.getStreet());
    ccstmt.setLong(nStartFrom + 1, address.getCityID());
    ccstmt.setString(nStartFrom + 2, address.getCity());
    ccstmt.setLong(nStartFrom + 3, address.getCountyID());
    ccstmt.setString(nStartFrom + 4, address.getCounty());
    ccstmt.setString(nStartFrom + 5, address.getRegionID());
    ccstmt.setString(nStartFrom + 6, address.getRegion());
    ccstmt.setLong(nStartFrom + 7, address.getCountryID());
    ccstmt.setString(nStartFrom + 8, address.getCountry());
    ccstmt.setString(nStartFrom + 9, address.getZIP());
    ccstmt.setString(nStartFrom + 10, address.getPhone());
    ccstmt.setString(nStartFrom + 11, address.getFax());
    ccstmt.setString(nStartFrom + 12, address.getEMail());
}

Ugly condition

2009-03-20T12:29:00.000+02:00

I have found a method for validating date:


// check that it is valid format
//    d,m,y
//    m,y
//    y
if ((nYearFrom != null && nMonthFrom != null && nDayFrom != null ||
     nYearFrom != null && nMonthFrom != null ||
     nYearFrom != null) &&
    (nYearTo != null && nMonthTo != null && nDayTo != null ||
     nYearTo != null && nMonthTo != null ||
     nYearTo != null))

After a short thinking, this condition can be simplified to:

if (nYearFrom != null && nYearTo != null)

File.separatorChar

2009-03-20T11:56:00.000+02:00

I have just found a funny snippet in Java code:

File pom = new File(dir.getAbsoluteFile()
  + String.valueOf(File.separatorChar) + "pom.xml");

Actualy class java.io.File has two constants:

public static final char separatorChar = '\';
public static final String separator = "" + separatorChar;

This is the same symbol, but separatorChar is a char, and separator is a String.

So, instead if using String.valueOf(File.separatorChar) developer could use File.separator.