Class AbstractTestMap

java.lang.Object
junit.framework.Assert
junit.framework.TestCase
All Implemented Interfaces:
Cloneable, junit.framework.Test
Direct Known Subclasses:
AbstractTestBidiMap, AbstractTestIterableMap, AbstractTestSortedMap

public abstract class AbstractTestMap extends AbstractTestObject
Abstract test class for Map methods and contracts.

The forces at work here are similar to those in AbstractTestCollection. If your class implements the full Map interface, including optional operations, simply extend this class, and implement the makeEmptyMap() method.

On the other hand, if your map implementation is weird, you may have to override one or more of the other protected methods. They're described below.

Entry Population Methods

Override these methods if your map requires special entries:

Supported Operation Methods

Override these methods if your map doesn't support certain operations:

Fixture Methods

For tests on modification operations (puts and removes), fixtures are used to verify that that operation results in correct state for the map and its collection views. Basically, the modification is performed against your map implementation, and an identical modification is performed against a confirmed map implementation. A confirmed map implementation is something like java.util.HashMap, which is known to conform exactly to the Map contract. After the modification takes place on both your map implementation and the confirmed map implementation, the two maps are compared to see if their state is identical. The comparison also compares the collection views to make sure they're still the same.

The upshot of all that is that any test that modifies the map in any way will verify that all of the map's state is still correct, including the state of its collection views. So for instance if a key is removed by the map's key set's iterator, then the entry set is checked to make sure the key/value pair no longer appears.

The map field holds an instance of your collection implementation. The entrySet, keySet and values fields hold that map's collection views. And the confirmed field holds an instance of the confirmed collection implementation. The resetEmpty() and resetFull() methods set these fields to empty or full maps, so that tests can proceed from a known state.

After a modification operation to both map and confirmed, the verify() method is invoked to compare the results. The verify() method calls separate methods to verify the map and its three collection views (verifyMap(), verifyEntrySet(), verifyKeySet(), and verifyValues()). You may want to override one of the verification methodsto perform additional verifications. For instance, TestDoubleOrderedMap would want override its verifyValues() method to verify that the values are unique and in ascending order.

Other Notes

If your Map fails one of these tests by design, you may still use this base set of cases. Simply override the test case (method) your map fails and/or the methods that define the assumptions used by the test cases. For example, if your map does not allow duplicate values, override isAllowDuplicateValues() and have it return false

  • Field Details

    • map

      protected Map map
      Map created by reset().
    • entrySet

      protected Set entrySet
      Entry set of map created by reset().
    • keySet

      protected Set keySet
      Key set of map created by reset().
    • values

      protected Collection values
      Values collection of map created by reset().
    • confirmed

      protected Map confirmed
      HashMap created by reset().
  • Constructor Details

    • AbstractTestMap

      public AbstractTestMap(String testName)
      JUnit constructor.
      Parameters:
      testName - the test name
  • Method Details

    • isPutAddSupported

      public boolean isPutAddSupported()
      Returns true if the maps produced by makeEmptyMap() and makeFullMap() support the put and putAll operations adding new mappings.

      Default implementation returns true. Override if your collection class does not support put adding.

    • isPutChangeSupported

      public boolean isPutChangeSupported()
      Returns true if the maps produced by makeEmptyMap() and makeFullMap() support the put and putAll operations changing existing mappings.

      Default implementation returns true. Override if your collection class does not support put changing.

    • isSetValueSupported

      public boolean isSetValueSupported()
      Returns true if the maps produced by makeEmptyMap() and makeFullMap() support the setValue operation on entrySet entries.

      Default implementation returns isPutChangeSupported(). Override if your collection class does not support setValue but does support put changing.

    • isRemoveSupported

      public boolean isRemoveSupported()
      Returns true if the maps produced by makeEmptyMap() and makeFullMap() support the remove and clear operations.

      Default implementation returns true. Override if your collection class does not support removal operations.

    • isGetStructuralModify

      public boolean isGetStructuralModify()
      Returns true if the maps produced by makeEmptyMap() and makeFullMap() can cause structural modification on a get(). The example is LRUMap.

      Default implementation returns false. Override if your map class structurally modifies on get.

    • isSubMapViewsSerializable

      public boolean isSubMapViewsSerializable()
      Returns whether the sub map views of SortedMap are serializable. If the class being tested is based around a TreeMap then you should override and return false as TreeMap has a bug in deserialization.
      Returns:
      false
    • isAllowNullKey

      public boolean isAllowNullKey()
      Returns true if the maps produced by makeEmptyMap() and makeFullMap() supports null keys.

      Default implementation returns true. Override if your collection class does not support null keys.

    • isAllowNullValue

      public boolean isAllowNullValue()
      Returns true if the maps produced by makeEmptyMap() and makeFullMap() supports null values.

      Default implementation returns true. Override if your collection class does not support null values.

    • isAllowDuplicateValues

      public boolean isAllowDuplicateValues()
      Returns true if the maps produced by makeEmptyMap() and makeFullMap() supports duplicate values.

      Default implementation returns true. Override if your collection class does not support duplicate values.

    • getSampleKeys

      public Object[] getSampleKeys()
      Returns the set of keys in the mappings used to test the map. This method must return an array with the same length as getSampleValues() and all array elements must be different. The default implementation constructs a set of String keys, and includes a single null key if isAllowNullKey() returns true.
    • getOtherKeys

      public Object[] getOtherKeys()
    • getOtherValues

      public Object[] getOtherValues()
    • getOtherNonNullStringElements

      public Object[] getOtherNonNullStringElements()
      Returns a list of string elements suitable for return by getOtherKeys() or getOtherValues().

      Override getOtherElements to returnthe results of this method if your collection does not support heterogenous elements or the null element.

    • getSampleValues

      public Object[] getSampleValues()
      Returns the set of values in the mappings used to test the map. This method must return an array with the same length as getSampleKeys(). The default implementation constructs a set of String values and includes a single null value if isAllowNullValue() returns true, and includes two values that are the same if isAllowDuplicateValues() returns true.
    • getNewSampleValues

      public Object[] getNewSampleValues()
      Returns a the set of values that can be used to replace the values returned from getSampleValues(). This method must return an array with the same length as getSampleValues(). The values returned from this method should not be the same as those returned from getSampleValues(). The default implementation constructs a set of String values and includes a single null value if isAllowNullValue() returns true, and includes two values that are the same if isAllowDuplicateValues() returns true.
    • addSampleMappings

      public void addSampleMappings(Map m)
      Helper method to add all the mappings described by getSampleKeys() and getSampleValues().
    • makeEmptyMap

      public abstract Map makeEmptyMap()
      Return a new, empty Map to be used for testing.
      Returns:
      the map to be tested
    • makeFullMap

      public Map makeFullMap()
      Return a new, populated map. The mappings in the map should match the keys and values returned from getSampleKeys() and getSampleValues(). The default implementation uses makeEmptyMap() and calls addSampleMappings(java.util.Map) to add all the mappings to the map.
      Returns:
      the map to be tested
    • makeObject

      public Object makeObject()
      Implements the superclass method to return the map to be tested.
      Specified by:
      makeObject in class AbstractTestObject
      Returns:
      the map to be tested
    • makeConfirmedMap

      public Map makeConfirmedMap()
      Override to return a map other than HashMap as the confirmed map.
      Returns:
      a map that is known to be valid
    • cloneMapEntry

      public Map.Entry cloneMapEntry(Map.Entry entry)
      Creates a new Map Entry that is independent of the first and the map.
    • getCompatibilityVersion

      public String getCompatibilityVersion()
      Gets the compatability version, needed for package access.
      Overrides:
      getCompatibilityVersion in class AbstractTestObject
      Returns:
      The version, or null if this object shouldn't be tested for compatibility with previous versions.
    • testSampleMappings

      public void testSampleMappings()
      Test to ensure the test setup is working properly. This method checks to ensure that the getSampleKeys and getSampleValues methods are returning results that look appropriate. That is, they both return a non-null array of equal length. The keys array must not have any duplicate values, and may only contain a (single) null key if isNullKeySupported() returns true. The values array must only have a null value if useNullValue() is true and may only have duplicate values if isAllowDuplicateValues() returns true.
    • testMakeMap

      public void testMakeMap()
      Test to ensure that makeEmptyMap and makeFull returns a new non-null map with each invocation.
    • testMapIsEmpty

      public void testMapIsEmpty()
      Tests Map.isEmpty()
    • testMapSize

      public void testMapSize()
      Tests Map.size()
    • testMapClear

      public void testMapClear()
      Tests Map.clear(). If the map isRemoveSupported() can add and remove elements}, then Map.size() and Map.isEmpty() are used to ensure that map has no elements after a call to clear. If the map does not support adding and removing elements, this method checks to ensure clear throws an UnsupportedOperationException.
    • testMapContainsKey

      public void testMapContainsKey()
      Tests Map.containsKey(Object) by verifying it returns false for all sample keys on a map created using an empty map and returns true for all sample keys returned on a full map.
    • testMapContainsValue

      public void testMapContainsValue()
      Tests Map.containsValue(Object) by verifying it returns false for all sample values on an empty map and returns true for all sample values on a full map.
    • testMapEquals

      public void testMapEquals()
      Tests Map.equals(Object)
    • testMapGet

      public void testMapGet()
      Tests Map.get(Object)
    • testMapHashCode

      public void testMapHashCode()
      Tests Map.hashCode()
    • testMapToString

      public void testMapToString()
      Tests Map.toString(). Since the format of the string returned by the toString() method is not defined in the Map interface, there is no common way to test the results of the toString() method. Thereforce, it is encouraged that Map implementations override this test with one that checks the format matches any format defined in its API. This default implementation just verifies that the toString() method does not return null.
    • testEmptyMapCompatibility

      public void testEmptyMapCompatibility() throws Exception
      Compare the current serialized form of the Map against the canonical version in CVS.
      Throws:
      Exception
    • testFullMapCompatibility

      public void testFullMapCompatibility() throws Exception
      Compare the current serialized form of the Map against the canonical version in CVS.
      Throws:
      Exception
    • testMapPut

      public void testMapPut()
      Tests Map.put(Object, Object)
    • testMapPutNullKey

      public void testMapPutNullKey()
      Tests Map.put(null, value)
    • testMapPutNullValue

      public void testMapPutNullValue()
      Tests Map.put(null, value)
    • testMapPutAll

      public void testMapPutAll()
      Tests Map.putAll(map)
    • testMapRemove

      public void testMapRemove()
      Tests Map.remove(Object)
    • testValuesClearChangesMap

      public void testValuesClearChangesMap()
      Tests that the Map.values() collection is backed by the underlying map for clear().
    • testKeySetClearChangesMap

      public void testKeySetClearChangesMap()
      Tests that the Map.keySet() collection is backed by the underlying map for clear().
    • testEntrySetClearChangesMap

      public void testEntrySetClearChangesMap()
      Tests that the Map.entrySet() collection is backed by the underlying map for clear().
    • testEntrySetContains1

      public void testEntrySetContains1()
    • testEntrySetContains2

      public void testEntrySetContains2()
    • testEntrySetContains3

      public void testEntrySetContains3()
    • testEntrySetRemove1

      public void testEntrySetRemove1()
    • testEntrySetRemove2

      public void testEntrySetRemove2()
    • testEntrySetRemove3

      public void testEntrySetRemove3()
    • testValuesRemoveChangesMap

      public void testValuesRemoveChangesMap()
      Tests that the Map.values() collection is backed by the underlying map by removing from the values collection and testing if the value was removed from the map.

      We should really test the "vice versa" case--that values removed from the map are removed from the values collection--also, but that's a more difficult test to construct (lacking a "removeValue" method.)

      See bug 9573.

    • testKeySetRemoveChangesMap

      public void testKeySetRemoveChangesMap()
      Tests that the Map.keySet() set is backed by the underlying map by removing from the keySet set and testing if the key was removed from the map.
    • bulkTestMapEntrySet

      public BulkTest bulkTestMapEntrySet()
      Bulk test Map.entrySet(). This method runs through all of the tests in AbstractTestSet. After modification operations, verify() is invoked to ensure that the map and the other collection views are still valid.
      Returns:
      a AbstractTestSet instance for testing the map's entry set
    • bulkTestMapKeySet

      public BulkTest bulkTestMapKeySet()
      Bulk test Map.keySet(). This method runs through all of the tests in AbstractTestSet. After modification operations, verify() is invoked to ensure that the map and the other collection views are still valid.
      Returns:
      a AbstractTestSet instance for testing the map's key set
    • bulkTestMapValues

      public BulkTest bulkTestMapValues()
      Bulk test Map.values(). This method runs through all of the tests in AbstractTestCollection. After modification operations, verify() is invoked to ensure that the map and the other collection views are still valid.
      Returns:
      a AbstractTestCollection instance for testing the map's values collection
    • resetEmpty

      public void resetEmpty()
      Resets the map, entrySet, keySet, values and confirmed fields to empty.
    • resetFull

      public void resetFull()
      Resets the map, entrySet, keySet, values and confirmed fields to full.
    • verify

      public void verify()
      Verifies that map is still equal to confirmed. This method checks that the map is equal to the HashMap, and that the map's collection views are still equal to the HashMap's collection views. An equals test is done on the maps and their collection views; their size and isEmpty results are compared; their hashCodes are compared; and containsAll tests are run on the collection views.
    • verifyMap

      public void verifyMap()
    • verifyEntrySet

      public void verifyEntrySet()
    • verifyKeySet

      public void verifyKeySet()
    • verifyValues

      public void verifyValues()
    • tearDown

      public void tearDown() throws Exception
      Erases any leftover instance variables by setting them to null.
      Overrides:
      tearDown in class junit.framework.TestCase
      Throws:
      Exception