See the feedback: http://mail.openjdk.java.net/pipermail/swing-dev/2016-September/006643.html
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Hi,
I found an error in javax.swing.text.html.parser.NPrintWriter.
void javax.swing.text.html.parser.NPrintWriter.println(char[] array)

     public void println(char[] array) {
          if (this.numPrinted >= this.numLines) {
                return;
          }
          char[] partialArray = null;
          for (int i = 0; i < array.length; i++) {
                if (array[i] == '\n') {
                     this.numPrinted++;
                }
                if (this.numPrinted == this.numLines) {
/* ==> */ partialArray = new char[i]; /* missing code, without there will be a NPE */
                     System.arraycopy(array, 0, partialArray, 0, i);
                }
          }
          if (partialArray != null) {
                super.print(partialArray);
          }
          if (this.numPrinted == this.numLines) {
                return;
          }
          super.println(array);
          this.numPrinted++;
     }
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