package org.frameworkset.util;
import java.io.IOException;
import java.io.InputStream;
import java.security.MessageDigest;
public abstract class UpdateMessageDigestInputStream extends InputStream {
/**
* Update the message digest with the rest of the bytes in this stream.
* <p>Using this method is more optimized since it avoids creating new
* byte arrays for each call.
* @param messageDigest The message digest to update
* @throws IOException when propagated from {@link #read()}
*/
public void updateMessageDigest(MessageDigest messageDigest) throws IOException {
int data;
while ((data = read()) != -1){
messageDigest.update((byte) data);
}
}
/**
* Update the message digest with the next len bytes in this stream.
* <p>Using this method is more optimized since it avoids creating new
* byte arrays for each call.
* @param messageDigest The message digest to update
* @param len how many bytes to read from this stream and use to update the message digest
* @throws IOException when propagated from {@link #read()}
*/
public void updateMessageDigest(MessageDigest messageDigest, int len) throws IOException {
int data;
int bytesRead = 0;
while (bytesRead < len && (data = read()) != -1){
messageDigest.update((byte) data);
bytesRead++;
}
}
}