java - subclasses common methods implemented in abstract superclass with different constructors -

i know has been discussed here have add question. need make abstract class called abstractgraph, , has extended 2 types of graph implementations: 1 uses matrix, other 1 uses lists.

so far have this:

abstract class abstractgraph implements graph {      public void removealledges(){         //implementation here      }  } 

and subclasses:

public graphmatrix(){     graphmatrix()     {         //implementation matrix type      } }  public graphlist(){     graphlist()     {         //different implementation lists type     } } 

both implementations have same removealledges() method written same, guess has placed in abstract class. question is, how use references this inside abstract class ? have fill implementations getters , setters ? if so, benefit of using single implementation of method 2 (or more) subclasses.

you can use same code removealledges long not depend on underlying structure (e.g., matrix or list) or functionality implemented encapsulated methods use underlying graph structure (e.g., getters, setters, , other common methods may need). in perspective, latter methods abstract methods of class, since need implemented according underlying graph structure.

one of benefits code reuse. write once, , use in every graph implementation. in case have 2 graph classes, may end having multiple representations graphs depending on application. writing general methods nice way of saving time spent in coding, , helps maintain code in more efficient , organized way. debugging easier!!