Merge "Guarding collisions in TimeSparseArray" into pi-dev (b334f1b2) · Commits · e / os / android_frameworks_base

core/java/android/app/usage/TimeSparseArray.java

+22 −0

Original line number	Diff line number	Diff line
		@@ -17,6 +17,7 @@
		package android.app.usage;

		import android.util.LongSparseArray;
		import android.util.Slog;

		/**
		* An array that indexes by a long timestamp, representing milliseconds since the epoch.
		@@ -24,6 +25,8 @@ import android.util.LongSparseArray;
		* {@hide}
		*/
		public class TimeSparseArray<E> extends LongSparseArray<E> {
		private static final String TAG = TimeSparseArray.class.getSimpleName();

		public TimeSparseArray() {
		super();
		}
		@@ -69,6 +72,25 @@ public class TimeSparseArray<E> extends LongSparseArray<E> {
		}
		}

		/**
		* {@inheritDoc}
		*
		* Overridden to ensure no collisions. The key (time in milliseconds) is incremented till an
		* empty place is found.
		*/
		@Override
		public void put(long key, E value) {
		final long origKey = key;
		while (indexOfKey(key) >= 0) {
		key++;
		}
		if (origKey != key) {
		Slog.w(TAG, "Value " + value + " supposed to be inserted at " + origKey
		+ " displaced to " + key);
		}
		super.put(key, value);
		}

		/**
		* Finds the index of the first element whose timestamp is less than or equal to
		* the given time.

core/tests/coretests/src/android/app/usage/TimeSparseArrayTest.java

0 → 100644

+47 −0

Original line number	Diff line number	Diff line
		/*
		* Copyright (C) 2018 The Android Open Source Project
		*
		* Licensed under the Apache License, Version 2.0 (the "License");
		* you may not use this file except in compliance with the License.
		* You may obtain a copy of the License at
		*
		* http://www.apache.org/licenses/LICENSE-2.0
		*
		* Unless required by applicable law or agreed to in writing, software
		* distributed under the License is distributed on an "AS IS" BASIS,
		* WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
		* See the License for the specific language governing permissions and
		* limitations under the License.
		*/


		package android.app.usage;

		import static org.junit.Assert.assertTrue;

		import android.os.SystemClock;
		import android.support.test.filters.SmallTest;
		import android.support.test.runner.AndroidJUnit4;

		import org.junit.Test;
		import org.junit.runner.RunWith;

		@RunWith(AndroidJUnit4.class)
		@SmallTest
		public class TimeSparseArrayTest {
		@Test
		public void testDuplicateKeysNotDropped() {
		final TimeSparseArray<Integer> testTimeSparseArray = new TimeSparseArray<>();
		final long key = SystemClock.elapsedRealtime();
		for (int i = 0; i < 5; i++) {
		testTimeSparseArray.put(key, i);
		}
		for (int i = 0; i < 5; i++) {
		final int valueIndex = testTimeSparseArray.indexOfValue(i);
		assertTrue("Value " + i + " not found; intended key: " + key , valueIndex >= 0);
		final long keyForValue = testTimeSparseArray.keyAt(valueIndex);
		assertTrue("Value " + i + " stored too far (at " + keyForValue + ") from intended key "
		+ key, Math.abs(keyForValue - key) < 100);
		}
		}
		}