org.async.rmi.RMIUtil Maven / Gradle / Ivy
package org.async.rmi;
import org.async.rmi.modules.Util;
import java.io.ByteArrayOutputStream;
import java.io.DataOutputStream;
import java.io.IOException;
import java.lang.reflect.Method;
import java.security.DigestOutputStream;
import java.security.MessageDigest;
import java.security.NoSuchAlgorithmException;
import java.util.ArrayList;
import java.util.Arrays;
import java.util.Collections;
import java.util.List;
/**
* Created by Barak Bar Orion
* 12/10/14.
*/
public class RMIUtil implements Util {
/**
* Compute the "method hash" of a remote method. The method hash
* is a long containing the first 64 bits of the SHA digest from
* the UTF encoded string of the method name and descriptor.
*/
@Override
public long computeMethodHash(Method m) {
long hash = 0;
ByteArrayOutputStream sink = new ByteArrayOutputStream(127);
try {
MessageDigest md = MessageDigest.getInstance("SHA");
DataOutputStream out = new DataOutputStream(
new DigestOutputStream(sink, md));
String s = getMethodNameAndDescriptor(m);
out.writeUTF(s);
// use only the first 64 bits of the digest for the hash
out.flush();
byte hasharray[] = md.digest();
for (int i = 0; i < Math.min(8, hasharray.length); i++) {
hash += ((long) (hasharray[i] & 0xFF)) << (i * 8);
}
} catch (IOException ignore) {
/* can't happen, but be deterministic anyway. */
hash = -1;
} catch (NoSuchAlgorithmException complain) {
throw new SecurityException(complain.getMessage());
}
return hash;
}
@Override
public MarshalledObject[] marshalParams(Object[] params) throws IOException {
if (params == null) {
return null;
}
MarshalledObject[] res = new MarshalledObject[params.length];
for (int i = 0; i < params.length; i++) {
Object param = params[i];
res[i] = new MarshalledObject<>(param);
}
return res;
}
@Override
public Object[] unMarshalParams(MarshalledObject[] params) throws IOException, ClassNotFoundException {
if (params == null) {
return null;
}
Object[] res = new Object[params.length];
for (int i = 0; i < params.length; i++) {
MarshalledObject param = params[i];
res[i] = param.get();
}
return res;
}
@Override
public List getSortedMethodList(Class[] remoteInterfaces) {
ArrayList methodList = new ArrayList<>();
for (Class cl : remoteInterfaces) {
methodList.addAll(Arrays.asList(cl.getMethods()));
}
methodList.trimToSize();
Collections.sort(methodList, (m1, m2) -> m1.toString().compareTo(m2.toString()));
return methodList;
}
private String getTypeDescriptor(Class type) {
if (type.isPrimitive()) {
if (type == int.class) {
return "I";
} else if (type == boolean.class) {
return "Z";
} else if (type == byte.class) {
return "B";
} else if (type == char.class) {
return "C";
} else if (type == short.class) {
return "S";
} else if (type == long.class) {
return "J";
} else if (type == float.class) {
return "F";
} else if (type == double.class) {
return "D";
} else if (type == void.class) {
return "V";
} else {
throw new Error("unrecognized primitive type: " + type);
}
} else if (type.isArray()) {
return type.getName().replace('.', '/');
} else {
return "L" + type.getName().replace('.', '/') + ";";
}
}
private String getMethodNameAndDescriptor(Method method) {
StringBuilder desc = new StringBuilder(method.getName());
desc.append('(');
Class[] paramTypes = method.getParameterTypes();
for (Class paramType : paramTypes) {
desc.append(getTypeDescriptor(paramType));
}
desc.append(')');
Class returnType = method.getReturnType();
if (returnType == void.class) {
desc.append('V');
} else {
desc.append(getTypeDescriptor(returnType));
}
return desc.toString();
}
}