package org.mongodb.morphia.aggregation;

public class Accumulator {
    private final String operation;
    private final String field;

    public Accumulator(final String operation, final String field) {
        this.operation = operation;
        this.field = "$" + field;
    }

    public String getField() {
        return field;
    }

    public String getOperation() {
        return operation;
    }
}

@@ -112,30 +112,30 @@
 ivate final 
-String
+Object
  field;%0A%0A   
@@ -196,24 +196,149 @@
 ng field) %7B%0A
+        this(operation, (Object)(%22$%22 + field));%0A    %7D%0A%09%0A    public Accumulator(final String operation, final Object field) %7B%0A
         this
@@ -385,14 +385,8 @@
 ld =
- %22$%22 +
  fie
@@ -403,30 +403,30 @@
 %0A    public 
-String
+Object
  getField() 

Allow Proper Implementation of Accumulator Sum