eventlog java_EventLog.java

package android.util;

import java.io.BufferedReader;

import java.io.FileReader;

import java.io.IOException;

import java.io.UnsupportedEncodingException;

import java.nio.BufferUnderflowException;

import java.nio.ByteBuffer;

import java.nio.ByteOrder;

import java.util.Collection;

import java.util.HashMap;

import java.util.regex.Matcher;

import java.util.regex.Pattern;

public class EventLog {

public EventLog() {}

private static final String TAG = "EventLog";

private static final String TAGS_FILE = "/system/etc/event-log-tags";

private static final String COMMENT_PATTERN = "^\\s*(#.*)?$";

private static final String TAG_PATTERN = "^\\s*(\\d+)\\s+(\\w+)\\s*(\\(.*\\))?\\s*$";

private static HashMapsTagCodes = null;

private static HashMapsTagNames = null;

public static final class Event {

private final ByteBuffer mBuffer;

// Layout of event log entry received from kernel.

private static final int LENGTH_OFFSET = 0;

private static final int PROCESS_OFFSET = 4;

private static final int THREAD_OFFSET = 8;

private static final int SECONDS_OFFSET = 12;

private static final int NANOSECONDS_OFFSET = 16;

private static final int PAYLOAD_START = 20;

private static final int TAG_OFFSET = 20;

private static final int DATA_START = 24;

// Value types

private static final byte INT_TYPE = 0;

private static final byte LONG_TYPE = 1;

private static final byte STRING_TYPE = 2;

private static final byte LIST_TYPE = 3;

Event(byte[] data) {

mBuffer = ByteBuffer.wrap(data);

mBuffer.order(ByteOrder.nativeOrder());

}

public int getProcessId() {

return mBuffer.getInt(PROCESS_OFFSET);

}

public int getThreadId() {

return mBuffer.getInt(THREAD_OFFSET);

}

public long getTimeNanos() {

return mBuffer.getInt(SECONDS_OFFSET) * 1000000000l

+ mBuffer.getInt(NANOSECONDS_OFFSET);

}

public int getTag() {

return mBuffer.getInt(TAG_OFFSET);

}

public synchronized Object getData() {

try {

mBuffer.limit(PAYLOAD_START + mBuffer.getShort(LENGTH_OFFSET));

mBuffer.position(DATA_START); // Just after the tag.

return decodeObject();

} catch (IllegalArgumentException e) {

Log.wtf(TAG, "Illegal entry payload: tag=" + getTag(), e);

return null;

} catch (BufferUnderflowException e) {

Log.wtf(TAG, "Truncated entry payload: tag=" + getTag(), e);

return null;

}

}

private Object decodeObject() {

byte type = mBuffer.get();

switch (type) {

case INT_TYPE:

return (Integer) mBuffer.getInt();

case LONG_TYPE:

return (Long) mBuffer.getLong();

case STRING_TYPE:

try {

int length = mBuffer.getInt();

int start = mBuffer.position();

mBuffer.position(start + length);

return new String(mBuffer.array(), start, length, "UTF-8");

} catch (UnsupportedEncodingException e) {

Log.wtf(TAG, "UTF-8 is not supported", e);

return null;

}

case LIST_TYPE:

int length = mBuffer.get();

if (length < 0) length += 256; // treat as signed byte

Object[] array = new Object[length];

for (int i = 0; i < length; ++i) array[i] = decodeObject();

return array;

default:

throw new IllegalArgumentException("Unknown entry type: " + type);

}

}

}

// We assume that the native methods deal with any concurrency issues.

public static native int writeEvent(int tag, int value);

public static native int writeEvent(int tag, long value);

public static native int writeEvent(int tag, String str);

public static native int writeEvent(int tag, Object... list);

public static native void readEvents(int[] tags, Collectionoutput)

throws IOException;

public static String getTagName(int tag) {

readTagsFile();

return sTagNames.get(tag);

}

public static int getTagCode(String name) {

readTagsFile();

Integer code = sTagCodes.get(name);

return code != null ? code : -1;

}

private static synchronized void readTagsFile() {

if (sTagCodes != null && sTagNames != null) return;

sTagCodes = new HashMap();

sTagNames = new HashMap();

Pattern comment = Pattern.compile(COMMENT_PATTERN);

Pattern tag = Pattern.compile(TAG_PATTERN);

BufferedReader reader = null;

String line;

try {

reader = new BufferedReader(new FileReader(TAGS_FILE), 256);

while ((line = reader.readLine()) != null) {

if (comment.matcher(line).matches()) continue;

Matcher m = tag.matcher(line);

if (!m.matches()) {

Log.wtf(TAG, "Bad entry in " + TAGS_FILE + ": " + line);

continue;

}

try {

int num = Integer.parseInt(m.group(1));

String name = m.group(2);

sTagCodes.put(name, num);

sTagNames.put(num, name);

} catch (NumberFormatException e) {

Log.wtf(TAG, "Error in " + TAGS_FILE + ": " + line, e);

}

}

} catch (IOException e) {

Log.wtf(TAG, "Error reading " + TAGS_FILE, e);

// Leave the maps existing but unpopulated

} finally {

try { if (reader != null) reader.close(); } catch (IOException e) {}

}

}

}

Java程序

|

258行

|

9.18 KB

package android.util;

import java.io.BufferedReader;

import java.io.FileReader;

import java.io.IOException;

import java.io.UnsupportedEncodingException;

import java.nio.BufferUnderflowException;

import java.nio.ByteBuffer;

import java.nio.ByteOrder;

import java.util.Collection;

import java.util.HashMap;

import java.util.regex.Matcher;

import java.util.regex.Pattern;

public class EventLog {

public EventLog() {}

private static final String TAG = "EventLog";

private static final String TAGS_FILE = "/system/etc/event-log-tags";

private static final String COMMENT_PATTERN = "^\\s*(#.*)?$";

private static final String TAG_PATTERN = "^\\s*(\\d+)\\s+(\\w+)\\s*(\\(.*\\))?\\s*$";

private static HashMap sTagCodes = null;

private static HashMap sTagNames = null;

public static final class Event {

private final ByteBuffer mBuffer;

// Layout of event log entry received from kernel.

private static final int LENGTH_OFFSET = 0;

private static final int PROCESS_OFFSET = 4;

private static final int THREAD_OFFSET = 8;

private static final int SECONDS_OFFSET = 12;

private static final int NANOSECONDS_OFFSET = 16;

private static final int PAYLOAD_START = 20;

private static final int TAG_OFFSET = 20;

private static final int DATA_START = 24;

// Value types

private static final byte INT_TYPE = 0;

private static final byte LONG_TYPE = 1;

private static final byte STRING_TYPE = 2;

private static final byte LIST_TYPE = 3;

Event(byte[] data) {

mBuffer = ByteBuffer.wrap(data);

mBuffer.order(ByteOrder.nativeOrder());

}

public int getProcessId() {

return mBuffer.getInt(PROCESS_OFFSET);

}

public int getThreadId() {

return mBuffer.getInt(THREAD_OFFSET);

}

public long getTimeNanos() {

return mBuffer.getInt(SECONDS_OFFSET) * 1000000000l

+ mBuffer.getInt(NANOSECONDS_OFFSET);

}

public int getTag() {

return mBuffer.getInt(TAG_OFFSET);

}

public synchronized Object getData() {

try {

mBuffer.limit(PAYLOAD_START + mBuffer.getShort(LENGTH_OFFSET));

mBuffer.position(DATA_START); // Just after the tag.

return decodeObject();

} catch (IllegalArgumentException e) {

Log.wtf(TAG, "Illegal entry payload: tag=" + getTag(), e);

return null;

} catch (BufferUnderflowException e) {

Log.wtf(TAG, "Truncated entry payload: tag=" + getTag(), e);

return null;

}

}

private Object decodeObject() {

byte type = mBuffer.get();

switch (type) {

case INT_TYPE:

return (Integer) mBuffer.getInt();

case LONG_TYPE:

return (Long) mBuffer.getLong();

case STRING_TYPE:

try {

int length = mBuffer.getInt();

int start = mBuffer.position();

mBuffer.position(start + length);

return new String(mBuffer.array(), start, length, "UTF-8");

} catch (UnsupportedEncodingException e) {

Log.wtf(TAG, "UTF-8 is not supported", e);

return null;

}

case LIST_TYPE:

int length = mBuffer.get();

if (length < 0) length += 256; // treat as signed byte

Object[] array = new Object[length];

for (int i = 0; i < length; ++i) array[i] = decodeObject();

return array;

default:

throw new IllegalArgumentException("Unknown entry type: " + type);

}

}

}

// We assume that the native methods deal with any concurrency issues.

public static native int writeEvent(int tag, int value);

public static native int writeEvent(int tag, long value);

public static native int writeEvent(int tag, String str);

public static native int writeEvent(int tag, Object... list);

public static native void readEvents(int[] tags, Collection output)

throws IOException;

public static String getTagName(int tag) {

readTagsFile();

return sTagNames.get(tag);

}

public static int getTagCode(String name) {

readTagsFile();

Integer code = sTagCodes.get(name);

return code != null ? code : -1;

}

private static synchronized void readTagsFile() {

if (sTagCodes != null && sTagNames != null) return;

sTagCodes = new HashMap();

sTagNames = new HashMap();

Pattern comment = Pattern.compile(COMMENT_PATTERN);

Pattern tag = Pattern.compile(TAG_PATTERN);

BufferedReader reader = null;

String line;

try {

reader = new BufferedReader(new FileReader(TAGS_FILE), 256);

while ((line = reader.readLine()) != null) {

if (comment.matcher(line).matches()) continue;

Matcher m = tag.matcher(line);

if (!m.matches()) {

Log.wtf(TAG, "Bad entry in " + TAGS_FILE + ": " + line);

continue;

}

try {

int num = Integer.parseInt(m.group(1));

String name = m.group(2);

sTagCodes.put(name, num);

sTagNames.put(num, name);

} catch (NumberFormatException e) {

Log.wtf(TAG, "Error in " + TAGS_FILE + ": " + line, e);

}

}

} catch (IOException e) {

Log.wtf(TAG, "Error reading " + TAGS_FILE, e);

// Leave the maps existing but unpopulated

} finally {

try { if (reader != null) reader.close(); } catch (IOException e) {}

}

}

}