What is the best way to test methods inside methods? (JUnit)

I am having a Java class A. A's constructor calls few methods m1,m2.

class A{

    public A(){
        m1(); 
        m2();
    ...... }

    public void m1(){...};
    public void m2(){...};
}

How to write tests for these methods? I generally write them as

class TestClass{

static A a = null;

public TestClass(){
    a = new A();
}

@Test
public testm1(){
   A.m1();
   //Some logic
}

However, these functions are called in the constructor itself. It looks like I am executing the method twice to check, and the constructor itself fails if the method is incorrectly written. What is the proper way of testing it?