Create a default constructor in Java

I need to create a method with a default constructor, which sets name to an empty开发者_运维百科 string and sets both credits and contactHours to zero. How to do it? Thanks, Pieter.

Methods don't have constructors... classes do. For example:

public class Dummy
{
    private int credits;
    private int contactHours;
    private String name;

    public Dummy()
    {
        name = "";
        credits = 0;
        contactHours = 0;
    }

    // More stuff here, e.g. property accessors
}

You don't really have to set credits or contactHours, as the int type defaults to 0 for fields anyway.

You're likely to want at least one constructor which takes initial values - in which case your parameterless one can delegate to that:

public class Dummy
{
    private String name;
    private int credits;
    private int contactHours;

    public Dummy()
    {
        this("", 0, 0);
    }

    public Dummy(String name, int credits, int contactHours)
    {
        this.name = name;
        this.credits = credits;
        this.contactHours = contactHours;
    }

    // More stuff here, e.g. property accessors
}

public class Test {
 private String name;
 private int credits;
 private int contactHours;

 public Test {

  this( "", 0, 0);

 }
public Test (String name, int credits, int contactHours) {
 this.name = name;
 this.credits = credits;
 this.contactHours = contactHours;
 }

// more code here
}

public class Bibabu{
  private String name;
  private int credits;
  private int contactHours;

  public Bibabu(){
    name = "";         // you could also write this.name and so on...
    credits = 0;
    contactHours= 0;
  }

  // more code here

}

You don't need a constructor:

public class Dummy
{
    private int credits = 0;
    private int contactHours=0;
    private String name="";
/*
    public Dummy()
    {
        name = "";
        credits = 0;
        contactHours = 0;
    }
*/  
    // More stuff here, e.g. property accessors
}

//constructor
     public Account(int id, double balance, Person owner){

        this.id = id;
        this.balance = balance;
        this.owner = owner;