Poll: Kiểm tra kiến thức Core Java (Garbage Collection )- 1.09

[qtd (Đỗ Trung Quân)]

When is the Float object, created in line 3, eligible for garbage collection?

public Object m() 
{  
    Object o = new Float(3.14F); 
    Object [] oa = new Object[l];
    oa[0] = o; /* Line 5 */
    o = null;  /* Line 6 */
    oa[0] = null; /* Line 7 */
    return o; /* Line 8 */
}

• A. just after line 5
• B. just after line 6
• C. just after line 7
• D. just after line 8

Answer:

Option C

[details=Explanation:]Option A is wrong. This simply copies the object reference into the array.
Option B is wrong. The reference o is set to null, but, oa[0] still maintains the reference to the Float object.
Option C is correct. The thread of execution will then not have access to the object.[/details]