core/java/android/net/NetworkStats.java - platform/frameworks/base - Gitiles

 /*
  * Copyright (C) 2011 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.net;

 import android.os.Parcel;
 import android.os.Parcelable;
 import android.os.SystemClock;
 import android.util.SparseBooleanArray;

 import java.io.CharArrayWriter;
 import java.io.PrintWriter;
 import java.util.HashSet;

 /**
  * Collection of active network statistics. Can contain summary details across
  * all interfaces, or details with per-UID granularity. Internally stores data
  * as a large table, closely matching {@code /proc/} data format. This structure
  * optimizes for rapid in-memory comparison, but consider using
  * {@link NetworkStatsHistory} when persisting.
  *
  * @hide
  */
 public class NetworkStats implements Parcelable {
     /** {@link #iface} value when interface details unavailable. */
     public static final String IFACE_ALL = null;
     /** {@link #uid} value when UID details unavailable. */
     public static final int UID_ALL = -1;

     // NOTE: data should only be accounted for once in this structure; if data
     // is broken out, the summarized version should not be included.

     /**
      * {@link SystemClock#elapsedRealtime()} timestamp when this data was
      * generated.
      */
     public final long elapsedRealtime;
     public final String[] iface;
     public final int[] uid;
     public final long[] rx;
     public final long[] tx;

     // TODO: add fg/bg stats once reported by kernel

     private NetworkStats(long elapsedRealtime, String[] iface, int[] uid, long[] rx, long[] tx) {
         this.elapsedRealtime = elapsedRealtime;
         this.iface = iface;
         this.uid = uid;
         this.rx = rx;
         this.tx = tx;
     }

     public NetworkStats(Parcel parcel) {
         elapsedRealtime = parcel.readLong();
         iface = parcel.createStringArray();
         uid = parcel.createIntArray();
         rx = parcel.createLongArray();
         tx = parcel.createLongArray();
     }

     public static class Builder {
         private long mElapsedRealtime;
         private final String[] mIface;
         private final int[] mUid;
         private final long[] mRx;
         private final long[] mTx;

         private int mIndex = 0;

         public Builder(long elapsedRealtime, int size) {
             mElapsedRealtime = elapsedRealtime;
             mIface = new String[size];
             mUid = new int[size];
             mRx = new long[size];
             mTx = new long[size];
         }

         public Builder addEntry(String iface, int uid, long rx, long tx) {
             mIface[mIndex] = iface;
             mUid[mIndex] = uid;
             mRx[mIndex] = rx;
             mTx[mIndex] = tx;
             mIndex++;
             return this;
         }

         public NetworkStats build() {
             if (mIndex != mIface.length) {
                 throw new IllegalArgumentException("unexpected number of entries");
             }
             return new NetworkStats(mElapsedRealtime, mIface, mUid, mRx, mTx);
         }
     }

     public int length() {
         // length is identical for all fields
         return iface.length;
     }

     /**
      * Find first stats index that matches the requested parameters.
      */
     public int findIndex(String iface, int uid) {
         final int length = length();
         for (int i = 0; i < length; i++) {
             if (equal(iface, this.iface[i]) && uid == this.uid[i]) {
                 return i;
             }
         }
         return -1;
     }

     /**
      * Return list of unique interfaces known by this data structure.
      */
     public String[] getUniqueIfaces() {
         final HashSet<String> ifaces = new HashSet<String>();
         for (String iface : this.iface) {
             if (iface != IFACE_ALL) {
                 ifaces.add(iface);
             }
         }
         return ifaces.toArray(new String[ifaces.size()]);
     }

     /**
      * Return list of unique UIDs known by this data structure.
      */
     public int[] getUniqueUids() {
         final SparseBooleanArray uids = new SparseBooleanArray();
         for (int uid : this.uid) {
             uids.put(uid, true);
         }

         final int size = uids.size();
         final int[] result = new int[size];
         for (int i = 0; i < size; i++) {
             result[i] = uids.keyAt(i);
         }
         return result;
     }

     /**
      * Subtract the given {@link NetworkStats}, effectively leaving the delta
      * between two snapshots in time. Assumes that statistics rows collect over
      * time, and that none of them have disappeared.
      *
      * @throws IllegalArgumentException when given {@link NetworkStats} is
      *             non-monotonic.
      */
     public NetworkStats subtract(NetworkStats value) {
         return subtract(value, true, false);
     }

     /**
      * Subtract the given {@link NetworkStats}, effectively leaving the delta
      * between two snapshots in time. Assumes that statistics rows collect over
      * time, and that none of them have disappeared.
      * <p>
      * Instead of throwing when counters are non-monotonic, this variant clamps
      * results to never be negative.
      */
     public NetworkStats subtractClamped(NetworkStats value) {
         return subtract(value, false, true);
     }

     /**
      * Subtract the given {@link NetworkStats}, effectively leaving the delta
      * between two snapshots in time. Assumes that statistics rows collect over
      * time, and that none of them have disappeared.
      *
      * @param enforceMonotonic Validate that incoming value is strictly
      *            monotonic compared to this object.
      * @param clampNegative Instead of throwing like {@code enforceMonotonic},
      *            clamp resulting counters at 0 to prevent negative values.
      */
     private NetworkStats subtract(
             NetworkStats value, boolean enforceMonotonic, boolean clampNegative) {
         final long deltaRealtime = this.elapsedRealtime - value.elapsedRealtime;
         if (enforceMonotonic && deltaRealtime < 0) {
             throw new IllegalArgumentException("found non-monotonic realtime");
         }

         // result will have our rows, and elapsed time between snapshots
         final int length = length();
         final NetworkStats.Builder result = new NetworkStats.Builder(deltaRealtime, length);
         for (int i = 0; i < length; i++) {
             final String iface = this.iface[i];
             final int uid = this.uid[i];

             // find remote row that matches, and subtract
             final int j = value.findIndex(iface, uid);
             if (j == -1) {
                 // newly appearing row, return entire value
                 result.addEntry(iface, uid, this.rx[i], this.tx[i]);
             } else {
                 // existing row, subtract remote value
                 long rx = this.rx[i] - value.rx[j];
                 long tx = this.tx[i] - value.tx[j];
                 if (enforceMonotonic && (rx < 0 || tx < 0)) {
                     throw new IllegalArgumentException("found non-monotonic values");
                 }
                 if (clampNegative) {
                     rx = Math.max(0, rx);
                     tx = Math.max(0, tx);
                 }
                 result.addEntry(iface, uid, rx, tx);
             }
         }

         return result.build();
     }

     private static boolean equal(Object a, Object b) {
         return a == b || (a != null && a.equals(b));
     }

     public void dump(String prefix, PrintWriter pw) {
         pw.print(prefix);
         pw.print("NetworkStats: elapsedRealtime="); pw.println(elapsedRealtime);
         for (int i = 0; i < iface.length; i++) {
             pw.print(prefix);
             pw.print("  iface="); pw.print(iface[i]);
             pw.print(" uid="); pw.print(uid[i]);
             pw.print(" rx="); pw.print(rx[i]);
             pw.print(" tx="); pw.println(tx[i]);
         }
     }

     @Override
     public String toString() {
         final CharArrayWriter writer = new CharArrayWriter();
         dump("", new PrintWriter(writer));
         return writer.toString();
     }

     /** {@inheritDoc} */
     public int describeContents() {
         return 0;
     }

     /** {@inheritDoc} */
     public void writeToParcel(Parcel dest, int flags) {
         dest.writeLong(elapsedRealtime);
         dest.writeStringArray(iface);
         dest.writeIntArray(uid);
         dest.writeLongArray(rx);
         dest.writeLongArray(tx);
     }

     public static final Creator<NetworkStats> CREATOR = new Creator<NetworkStats>() {
         public NetworkStats createFromParcel(Parcel in) {
             return new NetworkStats(in);
         }

         public NetworkStats[] newArray(int size) {
             return new NetworkStats[size];
         }
     };
 }
	/*
	* Copyright (C) 2011 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.net;

	import android.os.Parcel;
	import android.os.Parcelable;
	import android.os.SystemClock;
	import android.util.SparseBooleanArray;

	import java.io.CharArrayWriter;
	import java.io.PrintWriter;
	import java.util.HashSet;

	/**
	* Collection of active network statistics. Can contain summary details across
	* all interfaces, or details with per-UID granularity. Internally stores data
	* as a large table, closely matching {@code /proc/} data format. This structure
	* optimizes for rapid in-memory comparison, but consider using
	* {@link NetworkStatsHistory} when persisting.
	*
	* @hide
	*/
	public class NetworkStats implements Parcelable {
	/** {@link #iface} value when interface details unavailable. */
	public static final String IFACE_ALL = null;
	/** {@link #uid} value when UID details unavailable. */
	public static final int UID_ALL = -1;

	// NOTE: data should only be accounted for once in this structure; if data
	// is broken out, the summarized version should not be included.

	/**
	* {@link SystemClock#elapsedRealtime()} timestamp when this data was
	* generated.
	*/
	public final long elapsedRealtime;
	public final String[] iface;
	public final int[] uid;
	public final long[] rx;
	public final long[] tx;

	// TODO: add fg/bg stats once reported by kernel

	private NetworkStats(long elapsedRealtime, String[] iface, int[] uid, long[] rx, long[] tx) {
	this.elapsedRealtime = elapsedRealtime;
	this.iface = iface;
	this.uid = uid;
	this.rx = rx;
	this.tx = tx;
	}

	public NetworkStats(Parcel parcel) {
	elapsedRealtime = parcel.readLong();
	iface = parcel.createStringArray();
	uid = parcel.createIntArray();
	rx = parcel.createLongArray();
	tx = parcel.createLongArray();
	}

	public static class Builder {
	private long mElapsedRealtime;
	private final String[] mIface;
	private final int[] mUid;
	private final long[] mRx;
	private final long[] mTx;

	private int mIndex = 0;

	public Builder(long elapsedRealtime, int size) {
	mElapsedRealtime = elapsedRealtime;
	mIface = new String[size];
	mUid = new int[size];
	mRx = new long[size];
	mTx = new long[size];
	}

	public Builder addEntry(String iface, int uid, long rx, long tx) {
	mIface[mIndex] = iface;
	mUid[mIndex] = uid;
	mRx[mIndex] = rx;
	mTx[mIndex] = tx;
	mIndex++;
	return this;
	}

	public NetworkStats build() {
	if (mIndex != mIface.length) {
	throw new IllegalArgumentException("unexpected number of entries");
	}
	return new NetworkStats(mElapsedRealtime, mIface, mUid, mRx, mTx);
	}
	}

	public int length() {
	// length is identical for all fields
	return iface.length;
	}

	/**
	* Find first stats index that matches the requested parameters.
	*/
	public int findIndex(String iface, int uid) {
	final int length = length();
	for (int i = 0; i < length; i++) {
	if (equal(iface, this.iface[i]) && uid == this.uid[i]) {
	return i;
	}
	}
	return -1;
	}

	/**
	* Return list of unique interfaces known by this data structure.
	*/
	public String[] getUniqueIfaces() {
	final HashSet<String> ifaces = new HashSet<String>();
	for (String iface : this.iface) {
	if (iface != IFACE_ALL) {
	ifaces.add(iface);
	}
	}
	return ifaces.toArray(new String[ifaces.size()]);
	}

	/**
	* Return list of unique UIDs known by this data structure.
	*/
	public int[] getUniqueUids() {
	final SparseBooleanArray uids = new SparseBooleanArray();
	for (int uid : this.uid) {
	uids.put(uid, true);
	}

	final int size = uids.size();
	final int[] result = new int[size];
	for (int i = 0; i < size; i++) {
	result[i] = uids.keyAt(i);
	}
	return result;
	}

	/**
	* Subtract the given {@link NetworkStats}, effectively leaving the delta
	* between two snapshots in time. Assumes that statistics rows collect over
	* time, and that none of them have disappeared.
	*
	* @throws IllegalArgumentException when given {@link NetworkStats} is
	* non-monotonic.
	*/
	public NetworkStats subtract(NetworkStats value) {
	return subtract(value, true, false);
	}

	/**
	* Subtract the given {@link NetworkStats}, effectively leaving the delta
	* between two snapshots in time. Assumes that statistics rows collect over
	* time, and that none of them have disappeared.
	* <p>
	* Instead of throwing when counters are non-monotonic, this variant clamps
	* results to never be negative.
	*/
	public NetworkStats subtractClamped(NetworkStats value) {
	return subtract(value, false, true);
	}

	/**
	* Subtract the given {@link NetworkStats}, effectively leaving the delta
	* between two snapshots in time. Assumes that statistics rows collect over
	* time, and that none of them have disappeared.
	*
	* @param enforceMonotonic Validate that incoming value is strictly
	* monotonic compared to this object.
	* @param clampNegative Instead of throwing like {@code enforceMonotonic},
	* clamp resulting counters at 0 to prevent negative values.
	*/
	private NetworkStats subtract(
	NetworkStats value, boolean enforceMonotonic, boolean clampNegative) {
	final long deltaRealtime = this.elapsedRealtime - value.elapsedRealtime;
	if (enforceMonotonic && deltaRealtime < 0) {
	throw new IllegalArgumentException("found non-monotonic realtime");
	}

	// result will have our rows, and elapsed time between snapshots
	final int length = length();
	final NetworkStats.Builder result = new NetworkStats.Builder(deltaRealtime, length);
	for (int i = 0; i < length; i++) {
	final String iface = this.iface[i];
	final int uid = this.uid[i];

	// find remote row that matches, and subtract
	final int j = value.findIndex(iface, uid);
	if (j == -1) {
	// newly appearing row, return entire value
	result.addEntry(iface, uid, this.rx[i], this.tx[i]);
	} else {
	// existing row, subtract remote value
	long rx = this.rx[i] - value.rx[j];
	long tx = this.tx[i] - value.tx[j];
	if (enforceMonotonic && (rx < 0 \|\| tx < 0)) {
	throw new IllegalArgumentException("found non-monotonic values");
	}
	if (clampNegative) {
	rx = Math.max(0, rx);
	tx = Math.max(0, tx);
	}
	result.addEntry(iface, uid, rx, tx);
	}
	}

	return result.build();
	}

	private static boolean equal(Object a, Object b) {
	return a == b \|\| (a != null && a.equals(b));
	}

	public void dump(String prefix, PrintWriter pw) {
	pw.print(prefix);
	pw.print("NetworkStats: elapsedRealtime="); pw.println(elapsedRealtime);
	for (int i = 0; i < iface.length; i++) {
	pw.print(prefix);
	pw.print(" iface="); pw.print(iface[i]);
	pw.print(" uid="); pw.print(uid[i]);
	pw.print(" rx="); pw.print(rx[i]);
	pw.print(" tx="); pw.println(tx[i]);
	}
	}

	@Override
	public String toString() {
	final CharArrayWriter writer = new CharArrayWriter();
	dump("", new PrintWriter(writer));
	return writer.toString();
	}

	/** {@inheritDoc} */
	public int describeContents() {
	return 0;
	}

	/** {@inheritDoc} */
	public void writeToParcel(Parcel dest, int flags) {
	dest.writeLong(elapsedRealtime);
	dest.writeStringArray(iface);
	dest.writeIntArray(uid);
	dest.writeLongArray(rx);
	dest.writeLongArray(tx);
	}

	public static final Creator<NetworkStats> CREATOR = new Creator<NetworkStats>() {
	public NetworkStats createFromParcel(Parcel in) {
	return new NetworkStats(in);
	}

	public NetworkStats[] newArray(int size) {
	return new NetworkStats[size];
	}
	};
	}