Debug: Add setPropertiesOn(), and @hide it for now (1ce5bd34) · Commits · e / os / android_frameworks_base

core/java/android/os/Debug.java

+203 −1

Original line number	Diff line number	Diff line
		@@ -16,10 +16,20 @@

		package android.os;

		import com.android.internal.util.TypedProperties;

		import android.util.Config;
		import android.util.Log;

		import java.io.FileNotFoundException;
		import java.io.FileOutputStream;
		import java.io.FileReader;
		import java.io.IOException;
		import java.io.OutputStreamWriter;
		import java.io.PrintWriter;
		import java.io.Reader;
		import java.lang.reflect.Field;
		import java.lang.reflect.Modifier;

		import org.apache.harmony.dalvik.ddmc.Chunk;
		import org.apache.harmony.dalvik.ddmc.ChunkHandler;
		@@ -721,5 +731,197 @@ href="{@docRoot}guide/developing/tools/traceview.html">Traceview: A Graphical Lo
		count += mCounts[Opcodes.OP_INVOKE_SUPER_QUICK_RANGE];
		return count;
		}
		};
		}


		/**
		* A Map of typed debug properties.
		*/
		private static final TypedProperties debugProperties;

		/*
		* Load the debug properties from the standard files into debugProperties.
		*/
		static {
		if (Config.DEBUG) {
		final String TAG = "DebugProperties";
		final String[] files = { "/system/debug.prop", "/debug.prop", "/data/debug.prop" };
		final TypedProperties tp = new TypedProperties();

		// Read the properties from each of the files, if present.
		for (String file: files) {
		Reader r;
		try {
		r = new FileReader(file);
		} catch (FileNotFoundException ex) {
		// It's ok if a file is missing.
		continue;
		}

		Exception failure = null;
		try {
		tp.load(r);
		} catch (IOException ex) {
		failure = ex;
		} catch (TypedProperties.ParseException ex) {
		failure = ex;
		}
		if (failure != null) {
		throw new RuntimeException("Problem loading " + file, failure);
		}
		}

		debugProperties = tp.isEmpty() ? null : tp;
		} else {
		debugProperties = null;
		}
		}


		/**
		* Returns true if the type of the field matches the specified class.
		* Handles the case where the class is, e.g., java.lang.Boolean, but
		* the field is of the primitive "boolean" type. Also handles all of
		* the java.lang.Number subclasses.
		*/
		private static boolean fieldTypeMatches(Field field, Class<?> cl) {
		Class<?> fieldClass = field.getType();
		if (fieldClass == cl) {
		return true;
		}
		Field primitiveTypeField;
		try {
		/* All of the classes we care about (Boolean, Integer, etc.)
		* have a Class field called "TYPE" that points to the corresponding
		* primitive class.
		*/
		primitiveTypeField = cl.getField("TYPE");
		} catch (NoSuchFieldException ex) {
		return false;
		}
		try {
		return fieldClass == (Class<?>)primitiveTypeField.get(null);
		} catch (IllegalAccessException ex) {
		return false;
		}
		}


		/**
		* Looks up the property that corresponds to the field, and sets the field's value
		* if the types match.
		*/
		private static void modifyFieldIfSet(final Field field, final String propertyName) {
		if (field.getType() == java.lang.String.class) {
		int stringInfo = debugProperties.getStringInfo(propertyName);
		switch (stringInfo) {
		case TypedProperties.STRING_SET:
		// Handle as usual below.
		break;
		case TypedProperties.STRING_NULL:
		try {
		field.set(null, null); // null object for static fields; null string
		} catch (IllegalAccessException ex) {
		throw new IllegalArgumentException(
		"Cannot set field for " + propertyName, ex);
		}
		return;
		case TypedProperties.STRING_NOT_SET:
		return;
		case TypedProperties.STRING_TYPE_MISMATCH:
		throw new IllegalArgumentException(
		"Type of " + propertyName + " " +
		" does not match field type (" + field.getType() + ")");
		default:
		throw new IllegalStateException(
		"Unexpected getStringInfo(" + propertyName + ") return value " +
		stringInfo);
		}
		}
		Object value = debugProperties.get(propertyName);
		if (value != null) {
		if (!fieldTypeMatches(field, value.getClass())) {
		throw new IllegalArgumentException(
		"Type of " + propertyName + " (" + value.getClass() + ") " +
		" does not match field type (" + field.getType() + ")");
		}
		try {
		field.set(null, value); // null object for static fields
		} catch (IllegalAccessException ex) {
		throw new IllegalArgumentException(
		"Cannot set field for " + propertyName, ex);
		}
		}
		}


		/**
		* Reflectively sets static fields of a class based on internal debugging
		* properties. This method is a no-op if android.util.Config.DEBUG is
		* false.
		* <p>
		* <strong>NOTE TO APPLICATION DEVELOPERS</strong>: Config.DEBUG will
		* always be false in release builds. This API is typically only useful
		* for platform developers.
		* </p>
		* Class setup: define a class whose only fields are non-final, static
		* primitive types (except for "char") or Strings. In a static block
		* after the field definitions/initializations, pass the class to
		* this method, Debug.setPropertiesOn(). Example:
		* <pre>
		* package com.example;
		*
		* import android.os.Debug;
		*
		* public class MyDebugVars {
		* public static String s = "a string";
		* public static String s2 = "second string";
		* public static String ns = null;
		* public static boolean b = false;
		* public static int i = 5;
		* public static float f = 0.1f;
		* public static double d = 0.5d;
		*
		* // This MUST appear AFTER all fields are defined and initialized!
		* static {
		* Debug.setPropertiesOn(MyDebugVars.class);
		* }
		* }
		* </pre>
		* setPropertiesOn() may override the value of any field in the class based
		* on internal properties that are fixed at boot time.
		* <p>
		* These properties are only set during platform debugging, and are not
		* meant to be used as a general-purpose properties store.
		*
		* {@hide}
		*
		* @param cl The class to (possibly) modify
		* @throws IllegalArgumentException if any fields are final or non-static,
		* or if the type of the field does not match the type of
		* the internal debugging property value.
		*/
		public static void setPropertiesOn(Class<?> cl) {
		if (Config.DEBUG) {
		if (debugProperties != null) {
		/* Only look for fields declared directly by the class,
		* so we don't mysteriously change static fields in superclasses.
		*/
		for (Field field : cl.getDeclaredFields()) {
		final String propertyName = cl.getName() + "." + field.getName();
		boolean isStatic = Modifier.isStatic(field.getModifiers());
		boolean isFinal = Modifier.isFinal(field.getModifiers());
		if (!isStatic \|\| isFinal) {
		throw new IllegalArgumentException(propertyName +
		" must be static and non-final");
		}
		modifyFieldIfSet(field, propertyName);
		}
		}
		} else {
		Log.w("android.os.Debug",
		"setPropertiesOn(" + (cl == null ? "null" : cl.getName()) +
		") called in non-DEBUG build");
		}
		}
		}