@Override
	public int getSerializedATNSegmentLimit() {
		// 65535 is the class file format byte limit for a UTF-8 encoded string literal
		// 3 is the maximum number of bytes it takes to encode a value in the range 0-0xFFFF
		return 65535 / 3;
	}
The Java target can cache the code generation templates.
tool/src/org/antlr/v4/codegen/target/JavaTarget.java