Index: src/main/java/common/javax/swing/text/DefaultCaret.java =================================================================== --- src/main/java/common/javax/swing/text/DefaultCaret.java (revision 495368) +++ src/main/java/common/javax/swing/text/DefaultCaret.java (working copy) @@ -983,6 +983,9 @@ * */ public void setBlinkRate(final int i) { + if (i < 0) { + throw new IllegalArgumentException("Invalid delay: " + i); + } blinkRate = i; stopTimer(blinkTimer); if (blinkRate > 0) {