src/share/classes/java/awt/event/KeyEvent.java

@@ -28,10 +28,12 @@
 import java.awt.Component;
 import java.awt.GraphicsEnvironment;
 import java.awt.Toolkit;
 import java.io.IOException;
 import java.io.ObjectInputStream;
+import java.util.StringJoiner;
+
 import sun.awt.AWTAccessor;
 
 /**
  * An event which indicates that a keystroke occurred in a component.
  * <p>

@@ -1556,37 +1558,28 @@
      * @return string a text description of the combination of modifier
      *                keys that were held down during the event
      * @see InputEvent#getModifiersExText(int)
      */
     public static String getKeyModifiersText(int modifiers) {
-        StringBuilder buf = new StringBuilder();
+        StringJoiner buf = new StringJoiner("+");
         if ((modifiers & InputEvent.META_MASK) != 0) {
-            buf.append(Toolkit.getProperty("AWT.meta", "Meta"));
-            buf.append("+");
+            buf.add(Toolkit.getProperty("AWT.meta", "Meta"));
         }
         if ((modifiers & InputEvent.CTRL_MASK) != 0) {
-            buf.append(Toolkit.getProperty("AWT.control", "Ctrl"));
-            buf.append("+");
+            buf.add(Toolkit.getProperty("AWT.control", "Ctrl"));
         }
         if ((modifiers & InputEvent.ALT_MASK) != 0) {
-            buf.append(Toolkit.getProperty("AWT.alt", "Alt"));
-            buf.append("+");
+            buf.add(Toolkit.getProperty("AWT.alt", "Alt"));
         }
         if ((modifiers & InputEvent.SHIFT_MASK) != 0) {
-            buf.append(Toolkit.getProperty("AWT.shift", "Shift"));
-            buf.append("+");
+            buf.add(Toolkit.getProperty("AWT.shift", "Shift"));
         }
         if ((modifiers & InputEvent.ALT_GRAPH_MASK) != 0) {
-            buf.append(Toolkit.getProperty("AWT.altGraph", "Alt Graph"));
-            buf.append("+");
+            buf.add(Toolkit.getProperty("AWT.altGraph", "Alt Graph"));
         }
         if ((modifiers & InputEvent.BUTTON1_MASK) != 0) {
-            buf.append(Toolkit.getProperty("AWT.button1", "Button1"));
-            buf.append("+");
-        }
-        if (buf.length() > 0) {
-            buf.setLength(buf.length()-1); // remove trailing '+'
+            buf.add(Toolkit.getProperty("AWT.button1", "Button1"));
         }
         return buf.toString();
     }