public static InputStream getInputStream(String key) {
// System.out.println("returning " + key + " from file cache (cache size: " + cache.size() +
// ")");
byte[] bytes = cache.get(key);
if (bytes == null) return null;
return new ByteArrayInputStream(bytes);
}
public static void addToCache(String key, File fileToCache) {
// System.out.println("storing " + key + " on file cache (cache size: " + cache.size() + ")");
try {
InputStream is = new FileInputStream(fileToCache);
// Get the size of the file
long length = fileToCache.length();
// You cannot create an array using a long type.
// It needs to be an int type.
// Before converting to an int type, check
// to ensure that file is not larger than Integer.MAX_VALUE.
if (length > Integer.MAX_VALUE) {
// File is too large
}
// Create the byte array to hold the data
byte[] bytes = new byte[(int) length];
// Read in the bytes
int offset = 0;
int numRead = 0;
while (offset < bytes.length
&& (numRead = is.read(bytes, offset, bytes.length - offset)) >= 0) {
offset += numRead;
}
// Ensure all the bytes have been read in
if (offset < bytes.length) {
is.close();
throw new IOException("Could not completely read file " + fileToCache.getName());
}
// Close the input stream and return bytes
is.close();
cache.put(key, bytes);
} catch (Exception e) {
System.err.println("error adding to cache! " + e.getMessage());
e.printStackTrace();
}
}
public void clear() {
cache.clear();
}
public int size() {
if (cache != null) return cache.size();
else return -1;
}
