title: why public constructor should be provided in javabean class
body: <p>I heared rules of JavaBean, in which first and main rule is , for every JavaBean class explicitly programmer should provide public default constructor . 
  Please can anyone explain why do we need to provide default constructor for JavaBean</p>
  
  <p><strong>UPDATE :</strong> </p>
  
  <p>Please explain clearly, why jvm will not provide default constructor for JavaBeans and how jvm reacts on providing default constructor</p>