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A library jar that provides APIs for Applications written for the Google Android Platform.
/*
* Copyright (C) 2007 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 android.compat.annotation.UnsupportedAppUsage;
import android.os.Build;
import java.io.PrintWriter;
import java.lang.reflect.Field;
import java.lang.reflect.InvocationTargetException;
import java.lang.reflect.Method;
import java.lang.reflect.Modifier;
import java.util.Arrays;
import java.util.Collections;
import java.util.List;
import java.util.Locale;
import java.util.stream.Collectors;
/**
* Various utilities for debugging and logging.
*/
public class DebugUtils {
/** @hide */ public DebugUtils() {}
/**
* Filters objects against the ANDROID_OBJECT_FILTER
* environment variable. This environment variable can filter objects
* based on their class name and attribute values.
*
* Here is the syntax for ANDROID_OBJECT_FILTER:
*
* ClassName@attribute1=value1@attribute2=value2...
*
* Examples:
*
* - Select TextView instances:
TextView
* - Select TextView instances of text "Loading" and bottom offset of 22:
*
TextView@text=Loading.*@bottom=22
*
*
* The class name and the values are regular expressions.
*
* This class is useful for debugging and logging purpose:
*
* if (DEBUG) {
* if (DebugUtils.isObjectSelected(childView) && LOGV_ENABLED) {
* Log.v(TAG, "Object " + childView + " logged!");
* }
* }
*
*
* NOTE: This method is very expensive as it relies
* heavily on regular expressions and reflection. Calls to this method
* should always be stripped out of the release binaries and avoided
* as much as possible in debug mode.
*
* @param object any object to match against the ANDROID_OBJECT_FILTER
* environement variable
* @return true if object is selected by the ANDROID_OBJECT_FILTER
* environment variable, false otherwise
*/
public static boolean isObjectSelected(Object object) {
boolean match = false;
String s = System.getenv("ANDROID_OBJECT_FILTER");
if (s != null && s.length() > 0) {
String[] selectors = s.split("@");
// first selector == class name
if (object.getClass().getSimpleName().matches(selectors[0])) {
// check potential attributes
for (int i = 1; i < selectors.length; i++) {
String[] pair = selectors[i].split("=");
Class klass = object.getClass();
try {
Method declaredMethod = null;
Class parent = klass;
do {
declaredMethod = parent.getDeclaredMethod("get" +
pair[0].substring(0, 1).toUpperCase(Locale.ROOT) +
pair[0].substring(1),
(Class[]) null);
} while ((parent = klass.getSuperclass()) != null &&
declaredMethod == null);
if (declaredMethod != null) {
Object value = declaredMethod
.invoke(object, (Object[])null);
match |= (value != null ?
value.toString() : "null").matches(pair[1]);
}
} catch (NoSuchMethodException e) {
e.printStackTrace();
} catch (IllegalAccessException e) {
e.printStackTrace();
} catch (InvocationTargetException e) {
e.printStackTrace();
}
}
}
}
return match;
}
/** @hide */
@UnsupportedAppUsage(maxTargetSdk = Build.VERSION_CODES.P, trackingBug = 115609023)
public static void buildShortClassTag(Object cls, StringBuilder out) {
if (cls == null) {
out.append("null");
} else {
String simpleName = cls.getClass().getSimpleName();
if (simpleName == null || simpleName.isEmpty()) {
simpleName = cls.getClass().getName();
int end = simpleName.lastIndexOf('.');
if (end > 0) {
simpleName = simpleName.substring(end+1);
}
}
out.append(simpleName);
out.append('{');
out.append(Integer.toHexString(System.identityHashCode(cls)));
}
}
/** @hide */
public static void printSizeValue(PrintWriter pw, long number) {
float result = number;
String suffix = "";
if (result > 900) {
suffix = "KB";
result = result / 1024;
}
if (result > 900) {
suffix = "MB";
result = result / 1024;
}
if (result > 900) {
suffix = "GB";
result = result / 1024;
}
if (result > 900) {
suffix = "TB";
result = result / 1024;
}
if (result > 900) {
suffix = "PB";
result = result / 1024;
}
String value;
if (result < 1) {
value = String.format("%.2f", result);
} else if (result < 10) {
value = String.format("%.1f", result);
} else if (result < 100) {
value = String.format("%.0f", result);
} else {
value = String.format("%.0f", result);
}
pw.print(value);
pw.print(suffix);
}
/** @hide */
public static String sizeValueToString(long number, StringBuilder outBuilder) {
if (outBuilder == null) {
outBuilder = new StringBuilder(32);
}
float result = number;
String suffix = "";
if (result > 900) {
suffix = "KB";
result = result / 1024;
}
if (result > 900) {
suffix = "MB";
result = result / 1024;
}
if (result > 900) {
suffix = "GB";
result = result / 1024;
}
if (result > 900) {
suffix = "TB";
result = result / 1024;
}
if (result > 900) {
suffix = "PB";
result = result / 1024;
}
String value;
if (result < 1) {
value = String.format("%.2f", result);
} else if (result < 10) {
value = String.format("%.1f", result);
} else if (result < 100) {
value = String.format("%.0f", result);
} else {
value = String.format("%.0f", result);
}
outBuilder.append(value);
outBuilder.append(suffix);
return outBuilder.toString();
}
/**
* Use prefixed constants (static final values) on given class to turn value
* into human-readable string.
*
* @hide
*/
public static String valueToString(Class clazz, String prefix, int value) {
for (Field field : clazz.getDeclaredFields()) {
final int modifiers = field.getModifiers();
if (Modifier.isStatic(modifiers) && Modifier.isFinal(modifiers)
&& field.getType().equals(int.class) && field.getName().startsWith(prefix)) {
try {
if (value == field.getInt(null)) {
return constNameWithoutPrefix(prefix, field);
}
} catch (IllegalAccessException ignored) {
}
}
}
return Integer.toString(value);
}
/**
* Use prefixed constants (static final values) on given class to turn flags
* into human-readable string.
*
* @hide
*/
public static String flagsToString(Class clazz, String prefix, int flags) {
final StringBuilder res = new StringBuilder();
boolean flagsWasZero = flags == 0;
for (Field field : clazz.getDeclaredFields()) {
final int modifiers = field.getModifiers();
if (Modifier.isStatic(modifiers) && Modifier.isFinal(modifiers)
&& field.getType().equals(int.class) && field.getName().startsWith(prefix)) {
try {
final int value = field.getInt(null);
if (value == 0 && flagsWasZero) {
return constNameWithoutPrefix(prefix, field);
}
if (value != 0 && (flags & value) == value) {
flags &= ~value;
res.append(constNameWithoutPrefix(prefix, field)).append('|');
}
} catch (IllegalAccessException ignored) {
}
}
}
if (flags != 0 || res.length() == 0) {
res.append(Integer.toHexString(flags));
} else {
res.deleteCharAt(res.length() - 1);
}
return res.toString();
}
/**
* Gets human-readable representation of constants (static final values).
*
* @hide
*/
public static String constantToString(Class clazz, String prefix, int value) {
for (Field field : clazz.getDeclaredFields()) {
final int modifiers = field.getModifiers();
try {
if (Modifier.isStatic(modifiers) && Modifier.isFinal(modifiers)
&& field.getType().equals(int.class) && field.getName().startsWith(prefix)
&& field.getInt(null) == value) {
return constNameWithoutPrefix(prefix, field);
}
} catch (IllegalAccessException ignored) {
}
}
return prefix + Integer.toString(value);
}
private static String constNameWithoutPrefix(String prefix, Field field) {
return field.getName().substring(prefix.length());
}
/**
* Returns method names from current stack trace, where {@link StackTraceElement#getClass}
* starts with the given classes name
*
* @hide
*/
public static List callersWithin(Class cls, int offset) {
List result = Arrays.stream(Thread.currentThread().getStackTrace())
.skip(offset + 3)
.filter(st -> st.getClassName().startsWith(cls.getName()))
.map(StackTraceElement::getMethodName)
.collect(Collectors.toList());
Collections.reverse(result);
return result;
}
}