### Question:
Permutation { public boolean isIdentity() { for (int i = 0; i < this.values.length; i++) { if (this.values[i] != i) { return false; } } return true; } Permutation(int size);  Permutation(int... values);  Permutation(Permutation other); @Override boolean equals(Object other); @Override int hashCode(); boolean isIdentity(); int size(); int get(int index); int[] getValues(); int firstIndexOfDifference(Permutation other); List<Integer> getOrbit(int element); void set(int index, int value); void setTo(Permutation other); Permutation multiply(Permutation other); Permutation invert(); String toCycleString(); @Override String toString();  }### Answer:
@Test public void isIdentityTest() { int size = 4; Permutation p = new Permutation(size); Assert.assertTrue(p.isIdentity()); }