Never use null collections
Don't null out collections; clear() them instead.
Change-Id: I738fa4b2fe5cbb3a741ee85884eb02e13d3e85c5
diff --git a/src/com/android/telecomm/BinderDeallocator.java b/src/com/android/telecomm/BinderDeallocator.java
index ab7db25..ae62ec3 100644
--- a/src/com/android/telecomm/BinderDeallocator.java
+++ b/src/com/android/telecomm/BinderDeallocator.java
@@ -65,7 +65,7 @@
* The set of all known binders, either in use or potentially about to be used.
*/
@SuppressWarnings("rawtypes")
- private Set<ServiceBinder> mBinders = Sets.newHashSet();
+ private final Set<ServiceBinder> mBinders = Sets.newHashSet();
/**
* Accounts for the action entering a critical section (i.e. potentially needing access to
diff --git a/src/com/android/telecomm/CallServiceRepository.java b/src/com/android/telecomm/CallServiceRepository.java
index 5567e51..c55fbf2 100644
--- a/src/com/android/telecomm/CallServiceRepository.java
+++ b/src/com/android/telecomm/CallServiceRepository.java
@@ -98,7 +98,7 @@
* responses are received, the partial (potentially empty) set gets passed (to the switchboard)
* instead. Entries are removed from this set as providers are processed.
*/
- private Set<ComponentName> mOutstandingProviders;
+ private final Set<ComponentName> mOutstandingProviders = Sets.newHashSet();
/**
* The map of call-service wrappers keyed by their ComponentName. Used to ensure at most one
@@ -107,7 +107,7 @@
* include only active call services (ones that are associated with one or more active calls)
* upon {@link #purgeInactiveCallServices()} invocations.
*/
- private Map<ComponentName, CallServiceWrapper> mCallServices = Maps.newHashMap();
+ private final Map<ComponentName, CallServiceWrapper> mCallServices = Maps.newHashMap();
/**
* Persists the specified parameters.
@@ -149,7 +149,7 @@
mLookupId = lookupId;
mIsLookupInProgress = true;
- mOutstandingProviders = Sets.newHashSet();
+ mOutstandingProviders.clear();
for (ComponentName name : providerNames) {
mOutstandingProviders.add(name);
bindProvider(name);
@@ -347,7 +347,7 @@
*/
private void terminateLookup() {
mHandler.removeCallbacks(mLookupTerminator);
- mOutstandingProviders = null;
+ mOutstandingProviders.clear();
updateSwitchboard();
mIsLookupInProgress = false;
diff --git a/src/com/android/telecomm/CallServiceSelectorRepository.java b/src/com/android/telecomm/CallServiceSelectorRepository.java
index 13249c5..b286a79 100644
--- a/src/com/android/telecomm/CallServiceSelectorRepository.java
+++ b/src/com/android/telecomm/CallServiceSelectorRepository.java
@@ -91,7 +91,7 @@
* The set of bound call-service selectors. Only populated via initiateLookup scenarios.
* Selectors should only be removed upon unbinding.
*/
- private Set<ICallServiceSelector> mSelectorRegistry = Sets.newHashSet();
+ private final Set<ICallServiceSelector> mSelectorRegistry = Sets.newHashSet();
/**
* Stores the names of the selectors to bind to in one lookup cycle. The set size represents
@@ -103,7 +103,7 @@
* selectors do not require finding and hence are excluded from this set. Also note that
* selectors are removed from this set as they register.
*/
- private Set<ComponentName> mUnregisteredSelectors;
+ private final Set<ComponentName> mUnregisteredSelectors = Sets.newHashSet();
/**
* Persists the specified parameters and initializes the new instance.
@@ -136,7 +136,7 @@
mLookupId = lookupId;
mIsLookupInProgress = true;
- mUnregisteredSelectors = Sets.newHashSet();
+ mUnregisteredSelectors.clear();
for (ComponentName name : selectorNames) {
if (!mSelectorRegistry.contains(name)) {
diff --git a/src/com/android/telecomm/CallsManager.java b/src/com/android/telecomm/CallsManager.java
index 7381bdc..7102cf4 100644
--- a/src/com/android/telecomm/CallsManager.java
+++ b/src/com/android/telecomm/CallsManager.java
@@ -79,9 +79,9 @@
private VoicemailManager mVoicemailManager;
- private List<OutgoingCallValidator> mOutgoingCallValidators = Lists.newArrayList();
+ private final List<OutgoingCallValidator> mOutgoingCallValidators = Lists.newArrayList();
- private List<IncomingCallValidator> mIncomingCallValidators = Lists.newArrayList();
+ private final List<IncomingCallValidator> mIncomingCallValidators = Lists.newArrayList();
/**
* Initializes the required Telecomm components.
diff --git a/src/com/android/telecomm/OutgoingCallProcessor.java b/src/com/android/telecomm/OutgoingCallProcessor.java
index a0875c9..aa0a0bb 100644
--- a/src/com/android/telecomm/OutgoingCallProcessor.java
+++ b/src/com/android/telecomm/OutgoingCallProcessor.java
@@ -269,7 +269,7 @@
return;
}
- if (mCallServiceDescriptorIterator.hasNext()) {
+ if (mCallServiceDescriptorIterator != null && mCallServiceDescriptorIterator.hasNext()) {
CallServiceDescriptor descriptor = mCallServiceDescriptorIterator.next();
final CallServiceWrapper callService =
mCallServicesById.get(descriptor.getCallServiceId());
diff --git a/src/com/android/telecomm/Switchboard.java b/src/com/android/telecomm/Switchboard.java
index a9889c5..2ef58e3 100644
--- a/src/com/android/telecomm/Switchboard.java
+++ b/src/com/android/telecomm/Switchboard.java
@@ -94,14 +94,14 @@
* {@link CallServiceRepository}. Populated during call-service lookup cycles as part of the
* {@link #placeOutgoingCall} flow and cleared upon zero-remaining new/pending outgoing calls.
*/
- private Set<CallServiceWrapper> mCallServices;
+ private final Set<CallServiceWrapper> mCallServices = Sets.newHashSet();
/**
* The set of currently available call-service-selector implementations,
* see {@link CallServiceSelectorRepository}.
- * TODO(gilad): Null out once the active-call count goes to zero.
+ * TODO(gilad): Clear once the active-call count goes to zero.
*/
- private Set<ICallServiceSelector> mSelectors;
+ private final Set<ICallServiceSelector> mSelectors = Sets.newHashSet();
/**
* The current lookup-cycle ID used with the repositories. Incremented with each invocation
@@ -139,8 +139,8 @@
// reset, (5) the selector lookup completes but the call-services are missing. This should
// be okay since the call-service lookup completed. Specifically the already-available call
// services are cached and will be provided in response to the second lookup cycle.
- mCallServices = null;
- mSelectors = null;
+ mCallServices.clear();
+ mSelectors.clear();
mNewOutgoingCalls.add(call);
@@ -180,7 +180,8 @@
void setCallServices(Set<CallServiceWrapper> callServices) {
mBinderDeallocator.updateBinders(mCallServices);
- mCallServices = callServices;
+ mCallServices.clear();
+ mCallServices.addAll(callServices);
processNewOutgoingCalls();
}
@@ -202,7 +203,8 @@
// emergency calls) and order the entire set prior to the assignment below. If the
// built-in selectors can be implemented in a manner that does not require binding,
// that's probably preferred. May want to use a LinkedHashSet for the sorted set.
- mSelectors = selectors;
+ mSelectors.clear();
+ mSelectors.addAll(selectors);
processNewOutgoingCalls();
}
@@ -283,7 +285,7 @@
* Attempts to process the next new outgoing calls that have not yet been expired.
*/
private void processNewOutgoingCalls() {
- if (isNullOrEmpty(mCallServices) || isNullOrEmpty(mSelectors)) {
+ if (mCallServices.isEmpty() || mSelectors.isEmpty()) {
// At least one call service and one selector are required to process outgoing calls.
return;
}
@@ -305,9 +307,6 @@
* @param call The call to place.
*/
private void processNewOutgoingCall(Call call) {
- Preconditions.checkNotNull(mCallServices);
- Preconditions.checkNotNull(mSelectors);
-
// Convert to (duplicate-free) list to aid index-based iteration, see the comment under
// setSelectors regarding using LinkedHashSet instead.
List<ICallServiceSelector> selectors = Lists.newArrayList();
@@ -365,15 +364,4 @@
}
}
}
-
- /**
- * Determines whether or not the specified collection is either null or empty.
- *
- * @param collection Either null or the collection object to be evaluated.
- * @return True if the collection is null or empty.
- */
- @SuppressWarnings("rawtypes")
- private boolean isNullOrEmpty(Collection collection) {
- return collection == null || collection.isEmpty();
- }
}