Java Utililty Methods ArrayList Sum

Double sum = 0.0;
for (Double num : values) {
    sum += num;
return sum;

double sum = 0;
for (double value : values) {
    sum += value;
return sum;

double sum = 0.0;
for (double value : values)
    sum += value;
return sum;

double sum = 0;
for (int i = 0; i < a.size(); i++)
    sum += a.get(i).doubleValue();
return sum;

ArrayList<ArrayList<String>> valuesInColumns = valuesInColumns(lines);
ArrayList<String> result = new ArrayList<String>();
for (int i = 0; i < valuesInColumns.size(); i++) {
    ArrayList<String> values = valuesInColumns.get(i);
    Double sum = 0.0;
    for (String value : values) {
        try {
            sum = sum + Double.parseDouble(value);
...

ArrayList<Double> sumV = new ArrayList<Double>();
for (int i = 0; i < v1.size(); i++) {
    sumV.add(v1.get(i) + v2.get(i));
return sumV;