/*
* 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 okio;
import com.google.j2objc.LibraryNotLinkedError;
import java.lang.reflect.Method;
/**
* J2ObjC wrapper for java.security.MessageDigest, which avoids statically linking
* the JRE security subset library unless actually used.
*/
class MessageDigest {
Object messageDigest;
MessageDigest(String algorithm) {
try {
Class<?> cls = Class.forName("java.security.MessageDigest");
Method m = cls.getDeclaredMethod("getInstance", String.class);
messageDigest = m.invoke(null, algorithm);
} catch (ClassNotFoundException e) {
throw new LibraryNotLinkedError("Security support", "jre_security",
"JavaSecurityMessageDigest");
} catch (Exception e) {
// Only happens if the algorithm isn't supported, which isn't likely
// since this method is only used by okio, so the algorithms are known.
throw new AssertionError(e);
}
}
public byte[] digest() {
try {
Method m = messageDigest.getClass().getMethod("digest");
return (byte[]) m.invoke(messageDigest);
} catch (Exception e) {
throw new AssertionError(e);
}
}
public byte[] digest(byte[] data) {
try {
Method m = messageDigest.getClass().getMethod("digest", new byte[0].getClass());
return (byte[]) m.invoke(messageDigest, data);
} catch (Exception e) {
throw new AssertionError(e);
}
}
public void update(byte[] input, int offset, int len) {
try {
Method m = messageDigest.getClass().getMethod("update",
new byte[0].getClass(), Integer.TYPE, Integer.TYPE);
m.invoke(messageDigest, input, offset, len);
} catch (Exception e) {
throw new AssertionError(e);
}
}
static byte[] digest(String algorithm, byte[] data) {
return new MessageDigest(algorithm).digest(data);
}
}