private static String fileToString(ResourceFile file) throws IOException {
		BufferedReader reader = new BufferedReader(new InputStreamReader(file.getInputStream()));
		try {
			StringBuffer buffer = new StringBuffer();
			String line = null;
			while ((line = reader.readLine()) != null) {
				buffer.append(line);
			}
			return buffer.toString();
		}
		finally {
			reader.close();
		}
	}
Get the last message produced by the decompiler process.
If the message is non-null, it is probably an error
message, but not always.  It is better to use the
getErrorMessage method off of DecompileResults.
@return the message string or null
Ghidra/Features/Decompiler/src/main/java/ghidra/app/decompiler/DecompInterface.java