org.apache.tika.eval.textstats.TextSha256Signature Maven / Gradle / Ivy
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* Licensed to the Apache Software Foundation (ASF) under one or more
* contributor license agreements. See the NOTICE file distributed with
* this work for additional information regarding copyright ownership.
* The ASF licenses this file to You under the Apache License, Version 2.0
* (the "License"); you may not use this file except in compliance with
* the License. You may obtain a copy of the License at
*
* http://www.apache.org/licenses/LICENSE-2.0
*
* Unless required by applicable law or agreed to in writing, software
* distributed under the License is distributed on an "AS IS" BASIS,
* WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
* See the License for the specific language governing permissions and
* limitations under the License.
*/
package org.apache.tika.eval.textstats;
import org.apache.commons.codec.binary.Base32;
import org.apache.commons.codec.digest.DigestUtils;
import java.security.MessageDigest;
/**
* Calculates the base32 encoded SHA-256 checksum on the analyzed text
*/
public class TextSha256Signature implements BytesRefCalculator {
static Base32 BASE32 = new Base32();
@Override
public BytesRefCalcInstance getInstance() {
return new TextSha256Instance();
}
class TextSha256Instance implements BytesRefCalcInstance {
private MessageDigest messageDigest = DigestUtils.getSha256Digest();
@Override
public void update(byte[] bytes, int start, int len) {
messageDigest.update(bytes, start, len);
}
@Override
public String finish() {
return BASE32.encodeAsString(messageDigest.digest());
}
@Override
public Class getOuterClass() {
return TextSha256Signature.class;
}
}
}