#vulnerable code 
                                @Test
    public void testGetPropertyType() throws Exception {
        assertThat(TypeUtil.getPropertyType(A.class, "b.i").equals(Integer.class), equalTo(true));
        assertThat(TypeUtil.getPropertyType(A.class, "s").equals(String.class), equalTo(true));
    } 
                            #location 3 
                            #vulnerability type NULL_DEREFERENCE
#fixed code
                                @Test
    public void testGetPropertyType() throws Exception {
        assertThat(TypeUtil.getPropertyType(A.class, "b.i", "1").equals(Integer.class), equalTo(true));
        assertThat(TypeUtil.getPropertyType(A.class, "s", "2").equals(String.class), equalTo(true));
        TypeUtil.getPropertyType(A.class, "b.j", "3");
    }