Archive:Java/Programming tips

When to use methods

Only use methods when you have a reason to break-up code. You should only use them when the part you are putting into the method has no connection to any other part (or is called at a separate time from it). Methods should finish off a function by themselves. However, long methods can be broken down into shorter methods. They should still, however, follow the steps: no connection, etc.

Essentially, methods should not be used for every statement. You should not, however, put a huge 1000 line program into the main method... common sense.

About Arrays

Arrays should be used for variables that have something to do with each other. Basically, arrays are a list of variables, and arrays are a variable themselves. Here is how to make an array

[class][] [variable-name];
//Or...
int[] myInts;

To specify the length of an array:

myInts=new int[LENGTH];
//Put into one statement
int[] myInts = new int[LENGTH];

LENGTH = array size. It is simply how many items are in the array.

You need to initialize each part of the array. To "access" the members of the array:

myInts[2]==5;
int temp = myInts[3];

Note: Do NOT use arrays when the members have nothing to do with each other. This causes messy code!

Basic Tips for Improving Code

Tabbing

Tabbing is necessary to understand your code more easily. For example, the following is very hard to understand because of many reasons, one being tabs:

public
class MessyCoding extends Coding {public
static void main(String
args[]
){System.out.println
("This is messy coding. Don't do this");System.exit(0);}}

In much better format:

public class CleanCoding extends Coding {
   public static void main(String args[])
   {
      System.out.println("This is clean coding. DO THIS!!");
      System.exit(0);
   }
}

Notice that you actually can understand the code! Every single new block that has { and } should have contents that have an extra tab. Example:

public class CleanCoding extends Coding {
   public static void main(String args[])
   {
      try{
         try{
             ...;
         }
         ...;
      }
      ...;
   }
   ...;
}

When to press Enter

To make your code look good, you should insert one empty line between methods:

public void method1()
{

}

public void method2()
{

}

You should make a new line after every statement/declaration. If a statement is too long, you can break it down.

Good Comments

Good comments can help make your code look neat. They should tell what you are doing overall, not what you are doing on each line. For example, you can comment an if statement if it is kind of complex, but not every statement has to be commented:

if( x%2 == 0 && x > 0 && x < 1000 ) { // tests for parity, sign, and size
    System.out.println( "x is a positive, even, integer less than 1000" );

    if( x%3 == 0 ) // tests if divisible by 3
        x++;
}

An example of bad commenting would be:

if( i1 == i2 && i1 == i3 ) // Check if i1 is equal to i2 and i3
{
   System.out.println( "Yes" ); // Print Yes to the command line
   i1++; // Add 1 to i1
}

Project: Java

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