Error in version 1.3.0. Stacktrace:

java.lang.NoSuchMethodError: java.nio.CharBuffer.limit(I)Ljava/nio/CharBuffer;
	at org.owasp.encoder.Encode$Buffer.encode(Encode.java:1325)
	at org.owasp.encoder.Encode.encode(Encode.java:1237)
	at org.owasp.encoder.Encode.forXml(Encode.java:756)
	at org.owasp.encoder.Encode.forHtml(Encode.java:145)

Error line looks like
_input.limit(remaining).position(0);

where _input is CharBuffer. Method limit(int) differs in Java 8 and Java 9: in Java 8 it is final in the base class Buffer, and in Java 9 it is overriden in CharBuffer with covariant return type.

Seems that it is compiled against Java >= 9, so that limit(int) is linked to CharBuffer.limit(int) which is missing in Java 8.