equals and hashCode in JDK7

Test.java

package pl.project13;

import java.util.Objects;

/**
 * Date: 4/19/11
 *
 * @author Konrad Malawski
 */
public class Test {
  private String  name;
  private String  surname;
  private Integer age;

  public Test() {
  }

  public Test(String name, String surname, Integer age) {
    this.name = name;
    this.surname = surname;
    this.age = age;
  }

  public Test(String name, String surname) {
    this.name = name;
    this.surname = surname;
  }

  @Override
  public boolean equals(Object o) {
    if (this == o) return true;

    if (!(o instanceof Test)) return false;
//    if (o == null || getClass() != o.getClass()) return false;

    Test that = (Test) o;

    boolean result = true;
    result = result && Objects.equals(this.name, that.name);
    result = result && Objects.equals(this.surname, that.surname);
    result = result && Objects.equals(this.age, that.age);
    return result;
  }

  @Override
  public int hashCode() {
    return Objects.hash(name, surname, age);
  }
}

TestTest.java

package pl.project13;

import java.util.HashSet;
import java.util.Set;
import java.util.TreeSet;

import static junit.framework.Assert.assertEquals;
import static junit.framework.Assert.assertFalse;
import static junit.framework.Assert.assertTrue;

/**
 * Date: 4/19/11
 *
 * @author Konrad Malawski
 */
public class TestTest {

  @org.junit.Test
  public void testEquals() throws Exception {
    Test test = new Test("Konrad", "Malawski", 21);

    // true
    assertTrue(test.equals(test));

    assertTrue(test.equals(new Test("Konrad", "Malawski", 21)));

    // false
    assertFalse(test.equals(new Test("Wacław", "Malawski", 1825)));

    assertFalse(test.equals(new Test("Wacław", "Malawski")));

    assertFalse(test.equals(new Test()));

    assertFalse(test.equals(new Object()));

    assertFalse(test.equals(null));
  }

  @org.junit.Test
  public void testHashCodeOnCollections() throws Exception {
    Test test = new Test("Konrad", "Malawski", 21);

    int sizeBefore;
    int sizeAfter;

    Set<Test> treeSet = new HashSet<>();

    treeSet.add(test);
    sizeBefore = treeSet.size();

    treeSet.add(test);
    sizeAfter = treeSet.size();

    assertEquals(sizeBefore, sizeAfter);
  }

  @org.junit.Test
  public void testHashCodeOnCollectionsOtherObject() throws Exception {
    Test test = new Test("Konrad", "Malawski", 21);
    Test test2 = new Test("Konrad", "Malawski", 21);

    int sizeBefore;
    int sizeAfter;

    Set<Test> treeSet = new HashSet<>();

    treeSet.add(test);
    sizeBefore = treeSet.size();

    treeSet.add(test2);
    sizeAfter = treeSet.size();

    assertEquals(sizeBefore, sizeAfter);
  }
}