Question

If a class has two synchronized methods:

public class A {
    public synchronized int do1() {...}
    public synchronized void do2(int i) {...}
}

Will invoking these two methods in one line cause a deadlock?

A a = new A();
a.do2(a.do1());

Answer 1

Note that in your example, the two methods are not invoked concurrently.

There is a clear strict order between them – do2() cannot be invoked until do1() is done!

Also note, the code is equivalent to

A a = new A();
int temp = a.do1();
a.do2(temp);