### Question:
Region implements Parcelable, Serializable { public String toString() { StringBuilder sb = new StringBuilder(); int i = 1; for (Identifier identifier: mIdentifiers) { if (i > 1) { sb.append(" "); } sb.append("id"); sb.append(i); sb.append(": "); sb.append(identifier == null ? "null" : identifier.toString()); i++; } return sb.toString(); } Region(String uniqueId, Identifier id1, Identifier id2, Identifier id3);  Region(String uniqueId, List<Identifier> identifiers);  Region(String uniqueId, List<Identifier> identifiers, String bluetoothAddress);  Region(String uniqueId, String bluetoothAddress); protected  Region(Parcel in); Identifier getId1(); Identifier getId2(); Identifier getId3(); Identifier getIdentifier(int i); String getUniqueId(); String getBluetoothAddress(); boolean matchesBeacon(Beacon beacon); @Override int hashCode(); @Override boolean equals(Object other); boolean hasSameIdentifiers(Region region); String toString(); int describeContents(); void writeToParcel(Parcel out, int flags); @Override @Deprecated Region clone(); static final Parcelable.Creator<Region> CREATOR; }### Answer:
@Test public void testToString() { Region region = new Region("myRegion", Identifier.parse("1"), Identifier.parse("2"), null); assertEquals("id1: 1 id2: 2 id3: null", region.toString()); }