SparseDoubleArray (8bcb4c92) · Commits · e / os / android_frameworks_base

core/java/android/util/SparseDoubleArray.java

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		/*
		* Copyright (C) 2021 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.util;

		/**
		* SparseDoubleArrays map integers to doubles. Unlike a normal array of doubles,
		* there can be gaps in the indices. It is intended to be more memory efficient
		* than using a HashMap to map Integers to Doubles, both because it avoids
		* auto-boxing keys and values and its data structure doesn't rely on an extra entry object
		* for each mapping.
		*
		* <p>Note that this container keeps its mappings in an array data structure,
		* using a binary search to find keys. The implementation is not intended to be appropriate for
		* data structures
		* that may contain large numbers of items. It is generally slower than a traditional
		* HashMap, since lookups require a binary search and adds and removes require inserting
		* and deleting entries in the array. For containers holding up to hundreds of items,
		* the performance difference is not significant, less than 50%.</p>
		*
		* <p>It is possible to iterate over the items in this container using
		* {@link #keyAt(int)} and {@link #valueAt(int)}. Iterating over the keys using
		* <code>keyAt(int)</code> with ascending values of the index will return the
		* keys in ascending order, or the values corresponding to the keys in ascending
		* order in the case of <code>valueAt(int)</code>.</p>
		*
		* @see SparseLongArray
		*
		* @hide
		*/
		public class SparseDoubleArray implements Cloneable {
		/**
		* The int->double map, but storing the doubles as longs using
		* {@link Double#doubleToRawLongBits(double)}.
		*/
		private SparseLongArray mValues;

		/** Creates a new SparseDoubleArray containing no mappings. */
		public SparseDoubleArray() {
		this(10);
		}

		/**
		* Creates a new SparseDoubleArray, containing no mappings, that will not
		* require any additional memory allocation to store the specified
		* number of mappings. If you supply an initial capacity of 0, the
		* sparse array will be initialized with a light-weight representation
		* not requiring any additional array allocations.
		*/
		public SparseDoubleArray(int initialCapacity) {
		mValues = new SparseLongArray(initialCapacity);
		}

		@Override
		public SparseDoubleArray clone() {
		SparseDoubleArray clone = null;
		try {
		clone = (SparseDoubleArray) super.clone();
		clone.mValues = mValues.clone();
		} catch (CloneNotSupportedException cnse) {
		/* ignore */
		}
		return clone;
		}

		/**
		* Gets the double mapped from the specified key, or <code>0</code>
		* if no such mapping has been made.
		*/
		public double get(int key) {
		final int index = mValues.indexOfKey(key);
		if (index < 0) {
		return 0.0d;
		}
		return valueAt(index);
		}

		/**
		* Adds a mapping from the specified key to the specified value,
		* replacing the previous mapping from the specified key if there
		* was one.
		*/
		public void put(int key, double value) {
		mValues.put(key, Double.doubleToRawLongBits(value));
		}

		/**
		* Adds a mapping from the specified key to the specified value,
		* <b>adding</b> its value to the previous mapping from the specified key if there
		* was one.
		*
		* <p>This differs from {@link #put} because instead of replacing any previous value, it adds
		* (in the numerical sense) to it.
		*/
		public void add(int key, double summand) {
		final double oldValue = get(key);
		put(key, oldValue + summand);
		}

		/** Returns the number of key-value mappings that this SparseDoubleArray currently stores. */
		public int size() {
		return mValues.size();
		}

		/**
		* Given an index in the range <code>0...size()-1</code>, returns
		* the key from the <code>index</code>th key-value mapping that this
		* SparseDoubleArray stores.
		*
		* @see SparseLongArray#keyAt(int)
		*/
		public int keyAt(int index) {
		return mValues.keyAt(index);
		}

		/**
		* Given an index in the range <code>0...size()-1</code>, returns
		* the value from the <code>index</code>th key-value mapping that this
		* SparseDoubleArray stores.
		*
		* @see SparseLongArray#valueAt(int)
		*/
		public double valueAt(int index) {
		return Double.longBitsToDouble(mValues.valueAt(index));
		}

		/**
		* {@inheritDoc}
		*
		* <p>This implementation composes a string by iterating over its mappings.
		*/
		@Override
		public String toString() {
		if (size() <= 0) {
		return "{}";
		}

		StringBuilder buffer = new StringBuilder(size() * 34);
		buffer.append('{');
		for (int i = 0; i < size(); i++) {
		if (i > 0) {
		buffer.append(", ");
		}
		int key = keyAt(i);
		buffer.append(key);
		buffer.append('=');
		double value = valueAt(i);
		buffer.append(value);
		}
		buffer.append('}');
		return buffer.toString();
		}
		}

core/java/com/android/internal/os/BatteryStatsImpl.java

+1 −75

Original line number	Diff line number	Diff line
		@@ -89,6 +89,7 @@ import android.util.PrintWriterPrinter;
		import android.util.Printer;
		import android.util.Slog;
		import android.util.SparseArray;
		import android.util.SparseDoubleArray;
		import android.util.SparseIntArray;
		import android.util.SparseLongArray;
		import android.util.TimeUtils;
		@@ -12547,81 +12548,6 @@ public class BatteryStatsImpl extends BatteryStats {
		}
		}

		/**
		* SparseDoubleArray map integers to doubles.
		* Its implementation is the same as that of {@link SparseLongArray}; see there for details.
		*
		* @see SparseLongArray
		*/
		private static class SparseDoubleArray {
		/**
		* The int->double map, but storing the doubles as longs using
		* {@link Double.doubleToRawLongBits(double)}.
		*/
		private final SparseLongArray mValues = new SparseLongArray();

		/**
		* Gets the double mapped from the specified key, or <code>0</code>
		* if no such mapping has been made.
		*/
		public double get(int key) {
		if (mValues.indexOfKey(key) >= 0) {
		return Double.longBitsToDouble(mValues.get(key));
		}
		return 0;
		}

		/**
		* Adds a mapping from the specified key to the specified value,
		* replacing the previous mapping from the specified key if there
		* was one.
		*/
		public void put(int key, double value) {
		mValues.put(key, Double.doubleToRawLongBits(value));
		}

		/**
		* Adds a mapping from the specified key to the specified value,
		* <b>adding</b> to the previous mapping from the specified key if there
		* was one.
		*/
		public void add(int key, double summand) {
		final double oldValue = get(key);
		put(key, oldValue + summand);
		}

		/**
		* Returns the number of key-value mappings that this SparseDoubleArray
		* currently stores.
		*/
		public int size() {
		return mValues.size();
		}

		/**
		* Given an index in the range <code>0...size()-1</code>, returns
		* the key from the <code>index</code>th key-value mapping that this
		* SparseDoubleArray stores.
		*
		* @see SparseLongArray#keyAt(int)
		*/
		public int keyAt(int index) {
		return mValues.keyAt(index);
		}

		/**
		* Given an index in the range <code>0...size()-1</code>, returns
		* the value from the <code>index</code>th key-value mapping that this
		* SparseDoubleArray stores.
		*
		* @see SparseLongArray#valueAt(int)
		*/
		public double valueAt(int index) {
		return Double.longBitsToDouble(mValues.valueAt(index));
		}

		}

		/**
		* Read and record Rail Energy data.
		*/

core/tests/coretests/src/android/util/SparseDoubleArrayTest.java

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		/*
		* Copyright (C) 2021 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.util;

		import static org.junit.Assert.assertEquals;

		import androidx.test.filters.SmallTest;
		import androidx.test.runner.AndroidJUnit4;

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

		import java.util.Arrays;

		/**
		* Internal tests for {@link SparseDoubleArray}.
		*
		* Run using:
		* atest FrameworksCoreTests:android.util.SparseDoubleArrayTest
		*/
		@SmallTest
		@RunWith(AndroidJUnit4.class)
		public class SparseDoubleArrayTest {
		private static final double EXACT_PRECISION = 0;
		private static final double PRECISION = 0.000000001;

		@Test
		public void testPutGet() {
		final SparseDoubleArray sda = new SparseDoubleArray();
		assertEquals("Array should be empty", 0, sda.size());

		final int[] keys = {1, 6, -14, 53251, 5, -13412, 12, 0, 2};
		final double[] values = {7, -12.4, 7, Double.NEGATIVE_INFINITY, Double.POSITIVE_INFINITY,
		Double.NaN,
		4311236312.0 / 3431470161413514334123.0,
		431123636434132151313412.0 / 34323.0,
		0};
		for (int i = 0; i < keys.length; i++) {
		sda.put(keys[i], values[i]);
		}

		assertEquals("Wrong size array", keys.length, sda.size());
		// Due to the implementation, we actually expect EXACT double equality.
		for (int i = 0; i < keys.length; i++) {
		assertEquals("Wrong value at index " + i, values[i], sda.get(keys[i]), EXACT_PRECISION);
		}

		// Now check something that was never put in
		assertEquals("Wrong value for absent index", 0, sda.get(100000), EXACT_PRECISION);
		}

		@Test
		public void testAdd() {
		final SparseDoubleArray sda = new SparseDoubleArray();

		sda.put(4, 6.1);
		sda.add(4, -1.2);
		sda.add(2, -1.2);

		assertEquals(6.1 - 1.2, sda.get(4), PRECISION);
		assertEquals(-1.2, sda.get(2), PRECISION);
		}

		@Test
		public void testKeyValueAt() {
		final SparseDoubleArray sda = new SparseDoubleArray();

		final int[] keys = {1, 6, -14, 53251, 5, -13412, 12, 0, 2};
		final double[] values = {7, -12.4, 7, Double.NEGATIVE_INFINITY, Double.POSITIVE_INFINITY,
		Double.NaN,
		4311236312.0 / 3431470161413514334123.0,
		431123636434132151313412.0 / 34323.0,
		0};
		for (int i = 0; i < keys.length; i++) {
		sda.put(keys[i], values[i]);
		}

		// Sort the sample data.
		final ArrayMap<Integer, Double> map = new ArrayMap<>(keys.length);
		for (int i = 0; i < keys.length; i++) {
		map.put(keys[i], values[i]);
		}
		final int[] sortedKeys = Arrays.copyOf(keys, keys.length);
		Arrays.sort(sortedKeys);

		for (int i = 0; i < sortedKeys.length; i++) {
		final int expectedKey = sortedKeys[i];
		final double expectedValue = map.get(expectedKey);

		assertEquals("Wrong key at index " + i, expectedKey, sda.keyAt(i), PRECISION);
		assertEquals("Wrong value at index " + i, expectedValue, sda.valueAt(i), PRECISION);
		}
		}
		}