Java tutorial
/* * Copyright (C) 2009 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.content.pm; import android.os.Parcel; import android.os.Parcelable; import android.util.proto.ProtoOutputStream; /** * Definition of a single optional hardware or software feature of an Android * device. * <p> * This object is used to represent both features supported by a device and * features requested by an app. Apps can request that certain features be * available as a prerequisite to being installed through the * {@code uses-feature} tag in their manifests. * <p> * Starting in {@link android.os.Build.VERSION_CODES#N}, features can have a * version, which must always be backwards compatible. That is, a device * claiming to support version 3 of a specific feature must support apps * requesting version 1 of that feature. */ public class FeatureInfo implements Parcelable { /** * The name of this feature, for example "android.hardware.camera". If * this is null, then this is an OpenGL ES version feature as described * in {@link #reqGlEsVersion}. */ public String name; /** * If this object represents a feature supported by a device, this is the * maximum version of this feature supported by the device. The device * implicitly supports all older versions of this feature. * <p> * If this object represents a feature requested by an app, this is the * minimum version of the feature required by the app. * <p> * When a feature version is undefined by a device, it's assumed to be * version 0. */ public int version; /** * Default value for {@link #reqGlEsVersion}; */ public static final int GL_ES_VERSION_UNDEFINED = 0; /** * The GLES version used by an application. The upper order 16 bits represent the * major version and the lower order 16 bits the minor version. Only valid * if {@link #name} is null. */ public int reqGlEsVersion; /** * Set on {@link #flags} if this feature has been required by the application. */ public static final int FLAG_REQUIRED = 0x0001; /** * Additional flags. May be zero or more of {@link #FLAG_REQUIRED}. */ public int flags; public FeatureInfo() { } public FeatureInfo(FeatureInfo orig) { name = orig.name; version = orig.version; reqGlEsVersion = orig.reqGlEsVersion; flags = orig.flags; } @Override public String toString() { if (name != null) { return "FeatureInfo{" + Integer.toHexString(System.identityHashCode(this)) + " " + name + " v=" + version + " fl=0x" + Integer.toHexString(flags) + "}"; } else { return "FeatureInfo{" + Integer.toHexString(System.identityHashCode(this)) + " glEsVers=" + getGlEsVersion() + " fl=0x" + Integer.toHexString(flags) + "}"; } } @Override public int describeContents() { return 0; } @Override public void writeToParcel(Parcel dest, int parcelableFlags) { dest.writeString(name); dest.writeInt(version); dest.writeInt(reqGlEsVersion); dest.writeInt(flags); } /** @hide */ public void writeToProto(ProtoOutputStream proto, long fieldId) { long token = proto.start(fieldId); if (name != null) { proto.write(FeatureInfoProto.NAME, name); } proto.write(FeatureInfoProto.VERSION, version); proto.write(FeatureInfoProto.GLES_VERSION, getGlEsVersion()); proto.write(FeatureInfoProto.FLAGS, flags); proto.end(token); } public static final Creator<FeatureInfo> CREATOR = new Creator<FeatureInfo>() { @Override public FeatureInfo createFromParcel(Parcel source) { return new FeatureInfo(source); } @Override public FeatureInfo[] newArray(int size) { return new FeatureInfo[size]; } }; private FeatureInfo(Parcel source) { name = source.readString(); version = source.readInt(); reqGlEsVersion = source.readInt(); flags = source.readInt(); } /** * This method extracts the major and minor version of reqGLEsVersion attribute * and returns it as a string. Say reqGlEsVersion value of 0x00010002 is returned * as 1.2 * @return String representation of the reqGlEsVersion attribute */ public String getGlEsVersion() { int major = ((reqGlEsVersion & 0xffff0000) >> 16); int minor = reqGlEsVersion & 0x0000ffff; return String.valueOf(major) + "." + String.valueOf(minor); } }