1 /*
   2  * Copyright (c) 2015, Oracle and/or its affiliates. All rights reserved.
   3  * DO NOT ALTER OR REMOVE COPYRIGHT NOTICES OR THIS FILE HEADER.
   4  *
   5  * This code is free software; you can redistribute it and/or modify it
   6  * under the terms of the GNU General Public License version 2 only, as
   7  * published by the Free Software Foundation.  Oracle designates this
   8  * particular file as subject to the "Classpath" exception as provided
   9  * by Oracle in the LICENSE file that accompanied this code.
  10  *
  11  * This code is distributed in the hope that it will be useful, but WITHOUT
  12  * ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or
  13  * FITNESS FOR A PARTICULAR PURPOSE.  See the GNU General Public License
  14  * version 2 for more details (a copy is included in the LICENSE file that
  15  * accompanied this code).
  16  *
  17  * You should have received a copy of the GNU General Public License version
  18  * 2 along with this work; if not, write to the Free Software Foundation,
  19  * Inc., 51 Franklin St, Fifth Floor, Boston, MA 02110-1301 USA.
  20  *
  21  * Please contact Oracle, 500 Oracle Parkway, Redwood Shores, CA 94065 USA
  22  * or visit www.oracle.com if you need additional information or have any
  23  * questions.
  24  */
  25 
  26 package sun.java2d.marlin;
  27 
  28 import jdk.internal.misc.JavaLangAccess;
  29 import jdk.internal.misc.SharedSecrets;
  30 
  31 public final class MarlinUtils {
  32     // TODO: use sun.util.logging.PlatformLogger once in JDK9
  33     private static final java.util.logging.Logger log;
  34 
  35     static {
  36         if (MarlinConst.useLogger) {
  37             log = java.util.logging.Logger.getLogger("sun.java2d.marlin");
  38         } else {
  39             log = null;
  40         }
  41     }
  42 
  43     private MarlinUtils() {
  44         // no-op
  45     }
  46 
  47     public static void logInfo(final String msg) {
  48         if (MarlinConst.useLogger) {
  49             log.info(msg);
  50         } else if (MarlinConst.enableLogs) {
  51             System.out.print("INFO: ");
  52             System.out.println(msg);
  53         }
  54     }
  55 
  56     public static void logException(final String msg, final Throwable th) {
  57         if (MarlinConst.useLogger) {
  58 //            log.warning(msg, th);
  59             log.log(java.util.logging.Level.WARNING, msg, th);
  60         } else if (MarlinConst.enableLogs) {
  61             System.out.print("WARNING: ");
  62             System.out.println(msg);
  63             th.printStackTrace(System.err);
  64         }
  65     }
  66 
  67     // Returns the caller's class and method's name; best effort
  68     // if cannot infer, return the logger's name.
  69     static String getCallerInfo(String className) {
  70         String sourceClassName = null;
  71         String sourceMethodName = null;
  72 
  73         JavaLangAccess access = SharedSecrets.getJavaLangAccess();
  74         Throwable throwable = new Throwable();
  75         int depth = access.getStackTraceDepth(throwable);
  76 
  77         boolean lookingForClassName = true;
  78         for (int ix = 0; ix < depth; ix++) {
  79             // Calling getStackTraceElement directly prevents the VM
  80             // from paying the cost of building the entire stack frame.
  81             StackTraceElement frame = access.getStackTraceElement(throwable, ix);
  82             String cname = frame.getClassName();
  83             if (lookingForClassName) {
  84                 // Skip all frames until we have found the first frame having the class name.
  85                 if (cname.equals(className)) {
  86                     lookingForClassName = false;
  87                 }
  88             } else {
  89                 if (!cname.equals(className)) {
  90                     // We've found the relevant frame.
  91                     sourceClassName = cname;
  92                     sourceMethodName = frame.getMethodName();
  93                     break;
  94                 }
  95             }
  96         }
  97 
  98         if (sourceClassName != null) {
  99             return sourceClassName + " " + sourceMethodName;
 100         } else {
 101             return "unknown";
 102         }
 103     }
 104 }