code: /**
   * Copyright 2018 Alexey Ragozin
   *
   * 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 org.gridkit.jvmtool.hflame;
  
  import java.awt.Color;
  
  import org.gridkit.jvmtool.stacktrace.StackFrame;
  
  public class DefaultFrameColorChooser implements FrameColorChooser {
  
      private final int baseHue;
      private final int deltaHue;
  
      public DefaultFrameColorChooser() {
          baseHue = 12;
          deltaHue = 10;
      }
  
      @Override
      public int getFrameColor(String frame) {
          if (frame.startsWith("(")) {
              return -1;
          }
          int c = hashColor(baseHue, deltaHue, className(frame), methodName(frame));
          return c;
      }
  
      private String className(String frame) {
          int ch = frame.indexOf('(');
          if (ch >= 0) {
              frame = frame.substring(0, ch);
          }
          ch = frame.lastIndexOf('.');
          if (ch >= 0) {
              return frame.substring(0, ch);
          }
          else {
              return frame;
          }
      }
  
      private String methodName(String frame) {
          int ch = frame.indexOf('(');
          if (ch >= 0) {
              frame = frame.substring(0, ch);
          }
          ch = frame.lastIndexOf('.');
          if (ch >= 0) {
              return frame.substring(ch + 1);
          }
          else {
              return "";
          }
      }
  
      public static int hashColor(int baseHue, int deltaHue, String className, String methodName) {
          int hP = packageNameHash(className);
          int hC = classNameHash(className);
          int hM = methodName.hashCode();
  
          int hue = (0xFF) & (deltaHue == 0 ? baseHue : baseHue + (hP % (2 * deltaHue)) - deltaHue);
          int sat = 180 + (hC % 20) - 10;
          int lum = 220 + (hM % 20) - 10;
  
          int c = Color.HSBtoRGB(hue / 255f, sat / 255f, lum / 255f);
          return 0xFFFFFF & c;
      }
  
      public static int hashGrayColor(StackFrame sf) {
          int hC = classNameHash(sf.getClassName());
          int hM = sf.getMethodName().hashCode();
  
          int hue = 0;
          int sat = 0;
          int lum = 220 + ((hM + hC) % 20) - 10;
  
          int c = Color.HSBtoRGB(hue / 255f, sat / 255f, lum / 255f);
          return c;
      }
  
      private static int packageNameHash(String className) {
          int c = className.lastIndexOf('.');
          if (c >= 0) {
              return className.substring(0, c).hashCode();
          }
          else {
              return 0;
          }
      }
  
      private static int classNameHash(String className) {
          int c = className.lastIndexOf('.');
          if (c >= 0) {
              className = className.substring(c + 1);
          }
  
          c = className.indexOf('$');
          if (c >= 0) {
              int nhash = className.substring(0, c).hashCode();
              int shash = className.substring(c + 1).hashCode();
              return nhash + (shash % 10);
          }
          else {
              return className.hashCode();
          }
      }
  }
  