Calendar.getInstance().getTime() returning date in “GMT” instead of Default TimeZone

Question

Calendar c = Calendar.getInstance();
System.out.println(c.getTime());
c.set(2007, 0, 1);
System.out.println(c.getTime());

Output:

Answer 1

To talk about this interesting behaviour:

The source code from the Calendar class:

public final void set(int year, int month, int date)
{
    set(YEAR, year);
    set(MONTH, month);
    set(DATE, date);
}

Which leads to the set method:

public void set(int field, int value)
{
    // If the fields are partially normalized, calculate all the
    // fields before changing any fields.
    if (areFieldsSet && !areAllFieldsSet) {
        computeFields();
    }
    internalSet(field, value);
    isTimeSet = false;
    areFieldsSet = false;
    isSet[field] = true;
    stamp[field] = nextStamp++;
    if (nextStamp == Integer.MAX_VALUE) {
        adjustStamp();
    }
}

The interesting part here is the computeFields() method which has two implementation (one for Gregorian and one for Japenese calendar). These methods are quite complex but as far as I can see this is the only place where your Calendar instance may change time zone in your usecase.