Add call-stack reporting methods into Debug

Added two public methods to Debug. These methods return a String
indicating the caller (getCaller()) or callers (getCallers(int depth))
of the calling method. The String indicates the class, method and line
number of the caller(s). Similar to using Throwable.fillInStackTrace()
but much more concise.

Change-Id: I53d0085aa50e4501d28e8eb3ad5b91ef700ac218

1 files changed, 1 insertions, 24 deletions

diff --git a/services/java/com/android/server/wm/WindowManagerService.java b/services/java/com/android/server/wm/WindowManagerService.java
index 72aab7b..966f4c1 100644
--- a/services/java/com/android/server/wm/WindowManagerService.java
+++ b/services/java/com/android/server/wm/WindowManagerService.java
@@ -8129,7 +8129,7 @@ public class WindowManagerService extends IWindowManager.Stub
             boolean recoveringMemory) {
         if (DEBUG_WINDOW_TRACE) {
             Slog.v(TAG, "performLayoutAndPlaceSurfacesLockedInner: entry. Called by "
-                    + getCallers(3));
+                    + Debug.getCallers(3));
         }
         if (mDisplay == null) {
             Slog.i(TAG, "skipping performLayoutAndPlaceSurfacesLockedInner with no mDisplay");
@@ -9621,27 +9621,4 @@ public class WindowManagerService extends IWindowManager.Stub
         mH.sendMessage(mH.obtainMessage(H.BULK_UPDATE_PARAMETERS, bulkUpdateParams,
                 pendingLayoutChanges));
     }
-
-    /**
-     * Never call directly. Only call through getCallers(int) or getCaller(). Otherwise
-     * the depth will be off.
-     * @param depth What level stack to return.
-     * @return A String indicating who the caller of the method that calls this is.
-     */
-    static String getCaller(int depth) {
-        StackTraceElement caller = Thread.currentThread().getStackTrace()[5 + depth];
-        return caller.getClassName() + "." + caller.getMethodName() + ":" + caller.getLineNumber();
-    }
-
-    static String getCallers(final int depth) {
-        StringBuffer sb = new StringBuffer();
-        for (int i = 0; i < depth; i++) {
-            sb.append(getCaller(i)).append(" ");
-        }
-        return sb.toString();
-    }
-
-    static String getCaller() {
-        return getCallers(1);
-    }
 }