Simple and
robust.
Task
I need to
have several sets of methods of class, that can be invoked in special order
using fluent interface. For example I need to have always first init(int a) method in a chain. In a second
chain I need to have add(int a) and reset() methods. For the third chain I’d like to have dec(int a) and getValue() methods. getValue() method will return a result.
Solution
It’s good
idea to use inner classes.
package
org.sbelei;
public class
FluentInterfaceSample {
private
SecondChain chain2;
private
ThirdChain chain3;
private int value;
{
chain2 = new SecondChain();
chain3 = new ThirdChain();
}
public static
FluentInterfaceSample create(){
return new
FluentInterfaceSample();
}
public SecondChain
init(int start){
value = start;
return chain2;
}
class
SecondChain {
public
ThirdChain add(int a){
value += a;
return chain3;
}
public ThirdChain reset(){
value = 0;
return chain3;
}
}
class
ThirdChain {
public ThirdChain
dec(int b){
value -=b;
return chain3;
}
public int getValue(){
return value;
}
}
public static void main(String[]
args){
int b = create().init(31).add(12).dec(10).getValue();
System.out.println(b);
}
}
