public Budget addCostFiltersEntry(String key, java.util.List<String> value) {
        if (null == this.costFilters) {
            this.costFilters = new java.util.HashMap<String, java.util.List<String>>();
        }
        if (this.costFilters.containsKey(key))
            throw new IllegalArgumentException("Duplicated keys (" + key.toString() + ") are provided.");
        this.costFilters.put(key, value);
        return this;
    }
Add a single CostFilters entry

@see Budget#withCostFilters
@returns a reference to this object so that method calls can be chained together.
aws-java-sdk-budgets/src/main/java/com/amazonaws/services/budgets/model/Budget.java