Java Utililty Methods Map Merge

List of utility methods to do Map Merge

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Description

The list of methods to do Map Merge are organized into topic(s).

Method

voidmergeEnv(Map newEnv, Map env)
merge Env 
if (env != null) {
    env.forEach((k, v) -> newEnv.put(k, v));
voidmergeEnvironmentVariables(Map environmentSource, Map environmentDestination, String environmentVariable)
merge Environment Variables 
if (environmentSource == null) {
    return;
if (environmentSource.containsKey(environmentVariable)) {
    environmentDestination.put(environmentVariable, environmentDestination.get(environmentVariable) + ":"
            + environmentSource.get(environmentVariable));
voidmergeFamilies(Map familySource, Map familyTarget)
merge Families 
if (familySource == null) {
    return;
for (K key : familySource.keySet()) {
    if (!familyTarget.containsKey(key)) {
        familyTarget.put(key, familySource.get(key));
    } else {
        if (familyTarget.get(key).getClass() == Integer.class) {
...
Map>mergeFixedValueConditions(Map> left, Map> right)
merge Fixed Value Conditions 
right.keySet().forEach(columnName -> {
    Set<Object> newValues = right.get(columnName);
    if (newValues != null) {
        left.merge(columnName, newValues, (l, r) -> new HashSet<Object>() {
                addAll(l);
                addAll(r);
        });
});
return left;
voidmergeIfAbsent(Map map, Map toMerge)
Add all values of a map to another map, but onlfy if not already existing. 
for (Map.Entry<String, String> entry : toMerge.entrySet()) {
    putIfAbsent(map, entry.getKey(), entry.getValue());
    ;
MapmergeImportedPermissionsWithExistingPermissions( Map> existingRoleIdsToActionIds, Map importedRoleIdsToActionIds)
merge Imported Permissions With Existing Permissions 
Map<Long, String[]> mergedRoleIdsToActionIds = new HashMap<>();
for (Map.Entry<Long, Set<String>> roleIdsToActionIds : existingRoleIdsToActionIds.entrySet()) {
    long roleId = roleIdsToActionIds.getKey();
    if (importedRoleIdsToActionIds.containsKey(roleId)) {
        String[] actionIds = importedRoleIdsToActionIds.remove(roleId);
        mergedRoleIdsToActionIds.put(roleId, actionIds);
    } else {
        mergedRoleIdsToActionIds.put(roleId, new String[0]);
...
MapmergeListWithMap(List from, Map to)
merge List With Map 
for (Integer value : from) {
    Integer count = to.get(value);
    to.put(value, (count != null ? count + 1 : 1));
return to;
MapmergeMap(Map map, Object[]... pairs)
Merges the map with the new value and returns a new map. 
if (map == null) {
    map = new HashMap();
Map newMap = new HashMap(map);
for (Object[] pair : pairs) {
    newMap.put(pair[0], pair[1]);
return newMap;
...
PropertiesmergeMap(Map primaryValues, Map defaultValues)
Create a list of Properties containing all keys from two lists of given Propertiess. 
Properties result = new Properties();
if (defaultValues != null) {
    result.putAll(defaultValues);
if (primaryValues != null) {
    result.putAll(primaryValues);
return result;
...
MapmergeMap(Map first, Map second)
Merge in one map to another -all entries in the second map are merged into the first -overwriting any duplicate keys. 
first.putAll(second);
return first;