Add a MessageUtils class to convert int constants to strings. (a2a9ab94) · Commits · e / os / android_frameworks_base

core/java/com/android/internal/util/MessageUtils.java

0 → 100644

+127 −0

Original line number	Diff line number	Diff line
		/*
		* Copyright (C) 2016 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 com.android.internal.util;

		import android.os.Message;
		import android.util.Log;
		import android.util.SparseArray;

		import java.lang.reflect.Field;

		/**
		* Static utility class for dealing with {@link Message} objects.
		*/
		public class MessageUtils {

		private static final String TAG = MessageUtils.class.getSimpleName();
		private static final boolean DBG = false;

		/** Thrown when two different constants have the same value. */
		public static class DuplicateConstantError extends Error {
		private DuplicateConstantError() {}
		public DuplicateConstantError(String name1, String name2, int value) {
		super(String.format("Duplicate constant value: both %s and %s = %d",
		name1, name2, value));
		}
		}

		/**
		* Finds the names of integer constants. Searches the specified {@code classes}, looking for
		* accessible static integer fields whose names begin with one of the specified {@prefixes}.
		*
		* @param classes the classes to examine.
		* @prefixes only consider fields names starting with one of these prefixes.
		* @return a {@link SparseArray} mapping integer constants to their names.
		*/
		public static SparseArray<String> findMessageNames(Class[] classes, String[] prefixes) {
		SparseArray<String> messageNames = new SparseArray<>();
		for (Class c : classes) {
		String className = c.getName();
		if (DBG) Log.d(TAG, "Examining class " + className);

		Field[] fields;
		try {
		fields = c.getDeclaredFields();
		} catch (SecurityException e) {
		Log.e(TAG, "Can't list fields of class " + className);
		continue;
		}

		for (Field field : fields) {
		String name = field.getName();

		for (String prefix : prefixes) {
		// Does this look like a constant?
		if (!name.startsWith(prefix)) {
		continue;
		}

		try {
		// TODO: can we have the caller try to access the field instead, so we don't
		// expose constants it does not have access to?
		field.setAccessible(true);

		// Fetch the constant's value.
		int value;
		try {
		value = field.getInt(null);
		} catch (IllegalArgumentException \| ExceptionInInitializerError e) {
		// The field is not an integer (or short or byte), or c's static
		// initializer failed and we have no idea what its value is.
		// Either way, give up on this field.
		break;
		}

		// Check for duplicate values.
		String previousName = messageNames.get(value);
		if (previousName != null && !previousName.equals(name)) {
		throw new DuplicateConstantError(name, previousName, value);
		}

		messageNames.put(value, name);
		if (DBG) {
		Log.d(TAG, String.format("Found constant: %s.%s = %d",
		className, name, value));
		}
		} catch (SecurityException \| IllegalAccessException e) {
		// Not allowed to make the field accessible, or no access. Ignore.
		continue;
		}
		}
		}
		}
		return messageNames;
		}

		/**
		* Default prefixes for constants.
		*/
		public static final String[] DEFAULT_PREFIXES = {"CMD_", "EVENT_"};

		/**
		* Finds the names of integer constants. Searches the specified {@code classes}, looking for
		* accessible static integer values whose names begin with {@link #DEFAULT_PREFIXES}.
		*
		* @param classNames the classes to examine.
		* @prefixes only consider fields names starting with one of these prefixes.
		* @return a {@link SparseArray} mapping integer constants to their names.
		*/
		public static SparseArray<String> findMessageNames(Class[] classNames) {
		return findMessageNames(classNames, DEFAULT_PREFIXES);
		}
		}

services/net/java/android/net/dhcp/DhcpClient.java

+8 −27

Original line number	Diff line number	Diff line
		@@ -19,6 +19,7 @@ package android.net.dhcp;
		import com.android.internal.util.HexDump;
		import com.android.internal.util.Protocol;
		import com.android.internal.util.State;
		import com.android.internal.util.MessageUtils;
		import com.android.internal.util.StateMachine;
		import com.android.internal.util.WakeupMessage;

		@@ -32,7 +33,6 @@ import android.net.NetworkUtils;
		import android.os.IBinder;
		import android.os.INetworkManagementService;
		import android.os.Message;
		import android.os.PowerManager;
		import android.os.RemoteException;
		import android.os.ServiceManager;
		import android.os.SystemClock;
		@@ -40,16 +40,15 @@ import android.system.ErrnoException;
		import android.system.Os;
		import android.system.PacketSocketAddress;
		import android.util.Log;
		import android.util.SparseArray;
		import android.util.TimeUtils;

		import java.io.FileDescriptor;
		import java.io.IOException;
		import java.lang.Thread;
		import java.net.Inet4Address;
		import java.net.InetSocketAddress;
		import java.net.NetworkInterface;
		import java.net.SocketException;
		import java.nio.BufferUnderflowException;
		import java.nio.ByteBuffer;
		import java.util.Arrays;
		import java.util.Random;
		@@ -131,6 +130,11 @@ public class DhcpClient extends StateMachine {
		private static final int CMD_TIMEOUT = PRIVATE_BASE + 3;
		private static final int CMD_ONESHOT_TIMEOUT = PRIVATE_BASE + 4;

		// For message logging.
		private static final Class[] sMessageClasses = { DhcpClient.class };
		private static final SparseArray<String> sMessageNames =
		MessageUtils.findMessageNames(sMessageClasses);

		// DHCP parameters that we request.
		private static final byte[] REQUESTED_PARAMS = new byte[] {
		DHCP_SUBNET_MASK,
		@@ -460,30 +464,7 @@ public class DhcpClient extends StateMachine {
		}

		private String messageName(int what) {
		switch (what) {
		case CMD_START_DHCP:
		return "CMD_START_DHCP";
		case CMD_STOP_DHCP:
		return "CMD_STOP_DHCP";
		case CMD_RENEW_DHCP:
		return "CMD_RENEW_DHCP";
		case CMD_PRE_DHCP_ACTION:
		return "CMD_PRE_DHCP_ACTION";
		case CMD_PRE_DHCP_ACTION_COMPLETE:
		return "CMD_PRE_DHCP_ACTION_COMPLETE";
		case CMD_POST_DHCP_ACTION:
		return "CMD_POST_DHCP_ACTION";
		case CMD_KICK:
		return "CMD_KICK";
		case CMD_RECEIVED_PACKET:
		return "CMD_RECEIVED_PACKET";
		case CMD_TIMEOUT:
		return "CMD_TIMEOUT";
		case CMD_ONESHOT_TIMEOUT:
		return "CMD_ONESHOT_TIMEOUT";
		default:
		return Integer.toString(what);
		}
		return sMessageNames.get(what, Integer.toString(what));
		}

		private String messageToString(Message message) {

services/net/java/android/net/ip/IpManager.java

+9 −20

Original line number	Diff line number	Diff line
		@@ -16,6 +16,8 @@

		package android.net.ip;

		import com.android.internal.util.MessageUtils;

		import android.content.Context;
		import android.net.DhcpResults;
		import android.net.InterfaceConfiguration;
		@@ -30,6 +32,7 @@ import android.os.Message;
		import android.os.RemoteException;
		import android.os.ServiceManager;
		import android.util.Log;
		import android.util.SparseArray;

		import com.android.internal.annotations.GuardedBy;
		import com.android.internal.annotations.VisibleForTesting;
		@@ -61,6 +64,11 @@ public class IpManager extends StateMachine {
		private static final boolean DBG = true;
		private static final boolean VDBG = false;

		// For message logging.
		private static final Class[] sMessageClasses = { IpManager.class, DhcpClient.class };
		private static final SparseArray<String> sWhatToString =
		MessageUtils.findMessageNames(sMessageClasses);

		/**
		* Callbacks for handling IpManager events.
		*/
		@@ -306,26 +314,7 @@ public class IpManager extends StateMachine {

		@Override
		protected String getWhatToString(int what) {
		// TODO: Investigate switching to reflection.
		switch (what) {
		case CMD_STOP:
		return "CMD_STOP";
		case CMD_START:
		return "CMD_START";
		case CMD_CONFIRM:
		return "CMD_CONFIRM";
		case EVENT_PRE_DHCP_ACTION_COMPLETE:
		return "EVENT_PRE_DHCP_ACTION_COMPLETE";
		case EVENT_NETLINK_LINKPROPERTIES_CHANGED:
		return "EVENT_NETLINK_LINKPROPERTIES_CHANGED";
		case DhcpClient.CMD_PRE_DHCP_ACTION:
		return "DhcpClient.CMD_PRE_DHCP_ACTION";
		case DhcpClient.CMD_POST_DHCP_ACTION:
		return "DhcpClient.CMD_POST_DHCP_ACTION";
		case DhcpClient.CMD_ON_QUIT:
		return "DhcpClient.CMD_ON_QUIT";
		}
		return "UNKNOWN:" + Integer.toString(what);
		return sWhatToString.get(what, "UNKNOWN: " + Integer.toString(what));
		}

		@Override