synchronized FileCacheEntry getFileCacheEntry(String md5) {
		if (md5 == null) {
			return null;
		}
		FileCacheEntry fce = memCache.get(md5);
		if (fce == null) {
			fce = getFileByMD5(md5);
			if (fce != null) {
				fce.file.setLastModified(System.currentTimeMillis());
			}
		}
		return fce;
	}
Returns a {@link FileCacheEntry} for the matching file, based on its MD5, or
NULL if there is no matching file.
<p>
Tweaks the file's last modified time to implement a LRU.

@param md5 md5 string.
@return {@link FileCacheEntry} with a File and it's md5 string or {@code null} if no
matching file exists in cache.
Ghidra/Features/Base/src/main/java/ghidra/formats/gfilesystem/FileCache.java