gistfile1.txt

Compiled from "MyInterface.java"
public interface batik.MyInterface {
 public abstract java.util.List<java.lang.String> strings();

 public int totalLength(); // OBSERVERA DEFAULT METHOD I INTERFACE
   Code:
      0: iconst_0      
      1: istore_1      
      2: aload_0       
      3: invokeinterface #1,  1            // InterfaceMethod strings:()Ljava/util/List;
      8: invokeinterface #2,  1            // InterfaceMethod java/util/List.iterator:()Ljava/util/Iterator;
     13: astore_2      
     14: aload_2       
     15: invokeinterface #3,  1            // InterfaceMethod java/util/Iterator.hasNext:()Z
     20: ifeq          43
     23: aload_2       
     24: invokeinterface #4,  1            // InterfaceMethod java/util/Iterator.next:()Ljava/lang/Object;
     29: checkcast     #5                  // class java/lang/String
     32: astore_3      
     33: iload_1       
     34: aload_3       
     35: invokevirtual #6                  // Method java/lang/String.length:()I
     38: iadd          
     39: istore_1      
     40: goto          14
     43: iload_1       
     44: ireturn       
}
Compiled from "MyClass.java"
public class batik.MyClass implements batik.MyInterface {
 public batik.MyClass();
   Code:
      0: aload_0       
      1: invokespecial #1                  // Method java/lang/Object."<init>":()V
      4: return        

 public java.util.List<java.lang.String> strings();
   Code:
      0: iconst_3      
      1: anewarray     #2                  // class java/lang/String
      4: dup           
      5: iconst_0      
      6: ldc           #3                  // String 1
      8: aastore       
      9: dup           
     10: iconst_1      
     11: ldc           #4                  // String 22
     13: aastore       
     14: dup           
     15: iconst_2      
     16: ldc           #5                  // String 333
     18: aastore       
     19: invokestatic  #6                  // Method java/util/Arrays.asList:([Ljava/lang/Object;)Ljava/util/List;
     22: areturn       
}

AFTER REWRITE=======>

public interface batik.MyInterface { //  ======== PURE ABSTRACT INTERFACE =========
 public abstract java.util.List<java.lang.String> strings();

 public abstract int totalLength();
}
Compiled from "MyClass.java"
public class batik.MyClass implements batik.MyInterface {
 public batik.MyClass();
   Code:
      0: aload_0       
      1: invokespecial #11                 // Method java/lang/Object."<init>":()V
      4: return        

 public java.util.List<java.lang.String> strings();
   Code:
      0: iconst_3      
      1: anewarray     #15                 // class java/lang/String
      4: dup           
      5: iconst_0      
      6: ldc           #17                 // String 1
      8: aastore       
      9: dup           
     10: iconst_1      
     11: ldc           #19                 // String 22
     13: aastore       
     14: dup           
     15: iconst_2      
     16: ldc           #21                 // String 333
     18: aastore       
     19: invokestatic  #27                 // Method java/util/Arrays.asList:([Ljava/lang/Object;)Ljava/util/List;
     22: areturn       

 public int totalLength();  // ===== FORMER DEFAULT METHOD DELEGATES TO STATIC HELPER METHOD ======
   Code:
      0: aload_0       
      1: invokestatic  #34                 // Method batik/MyInterfacehelper.totalLength:(Lbatik/MyInterface;)I
      4: ireturn       
}

Compiled from "Hello.java"
public class batik.MyInterfacehelper {
  private batik.MyInterfacehelper();
    Code:
       0: aload_0       
       1: invokespecial #9                  // Method java/lang/Object."<init>":()V
       4: return        

  public static int totalLength(batik.MyInterface); // ======= HELPER METHOD =======
    Code:
       0: iconst_0      
       1: istore_1      
       2: aload_0       
       3: invokeinterface #17,  1           // InterfaceMethod batik/MyInterface.strings:()Ljava/util/List;
       8: invokeinterface #23,  1           // InterfaceMethod java/util/List.iterator:()Ljava/util/Iterator;
      13: astore_2      
      14: aload_2       
      15: invokeinterface #29,  1           // InterfaceMethod java/util/Iterator.hasNext:()Z
      20: ifeq          43
      23: aload_2       
      24: invokeinterface #33,  1           // InterfaceMethod java/util/Iterator.next:()Ljava/lang/Object;
      29: checkcast     #35                 // class java/lang/String
      32: astore_3      
      33: iload_1       
      34: aload_3       
      35: invokevirtual #39                 // Method java/lang/String.length:()I
      38: iadd          
      39: istore_1      
      40: goto          14
      43: iload_1       
      44: ireturn       
}