org.spring4gwt.server.RpcHelper.java Source code

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Here is the source code for org.spring4gwt.server.RpcHelper.java

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/*
 * Copyright 2014-2016 CyberVision, Inc.
 *
 * Licensed 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.spring4gwt.server;

import com.google.gwt.user.client.rpc.SerializationException;
import com.google.gwt.user.client.rpc.impl.AbstractSerializationStream;
import com.google.gwt.user.server.rpc.RPC;
import com.google.gwt.user.server.rpc.SerializationPolicy;

import org.apache.commons.logging.Log;
import org.apache.commons.logging.LogFactory;

import java.lang.reflect.InvocationTargetException;
import java.lang.reflect.Method;
import java.util.Arrays;

public class RpcHelper {

    private static final Log LOG = LogFactory.getLog(RpcHelper.class);

    private RpcHelper() {
    }

    public static String invokeAndEncodeResponse(Object target, Method serviceMethod, Object[] args,
            SerializationPolicy serializationPolicy) throws SerializationException {
        return invokeAndEncodeResponse(target, serviceMethod, args, serializationPolicy,
                AbstractSerializationStream.DEFAULT_FLAGS);
    }

    /**
     * Invoke the method on targeted object and encode received response.
     *
     * @param target              the target object
     * @param serviceMethod       the service method
     * @param args                the args of method
     * @param serializationPolicy the serialization policy
     * @param flags               the flags
     * @throws SerializationException the serialization exception
     */
    public static String invokeAndEncodeResponse(Object target, Method serviceMethod, Object[] args,
            SerializationPolicy serializationPolicy, int flags) throws SerializationException {
        if (serviceMethod == null) {
            throw new NullPointerException("serviceMethod");
        }

        if (serializationPolicy == null) {
            throw new NullPointerException("serializationPolicy");
        }

        String responsePayload;
        try {
            Object result = serviceMethod.invoke(target, args);

            responsePayload = RPC.encodeResponseForSuccess(serviceMethod, result, serializationPolicy, flags);

        } catch (IllegalAccessException ex) {
            SecurityException securityException = new SecurityException(
                    formatIllegalAccessErrorMessage(target, serviceMethod));
            securityException.initCause(ex);
            throw securityException;
        } catch (IllegalArgumentException ex) {
            SecurityException securityException = new SecurityException(
                    formatIllegalArgumentErrorMessage(target, serviceMethod, args));
            securityException.initCause(ex);
            throw securityException;
        } catch (InvocationTargetException ex) {
            // Try to encode the caught exception
            //
            Throwable cause = ex.getCause();

            LOG.error("Unexpected exception occured while invoking service method - " + serviceMethod.getName(),
                    ex);

            responsePayload = RPC.encodeResponseForFailure(serviceMethod, cause, serializationPolicy, flags);
        }

        return responsePayload;
    }

    private static String formatIllegalArgumentErrorMessage(Object target, Method serviceMethod, Object[] args) {
        StringBuffer sb = new StringBuffer();
        sb.append("Blocked attempt to invoke method '");
        sb.append(getSourceRepresentation(serviceMethod));
        sb.append("'");

        if (target != null) {
            sb.append(" on target '");
            sb.append(printTypeName(target.getClass()));
            sb.append("'");
        }

        sb.append(" with invalid arguments");

        if (args != null && args.length > 0) {
            sb.append(Arrays.asList(args));
        }

        return sb.toString();
    }

    private static String formatIllegalAccessErrorMessage(Object target, Method serviceMethod) {
        StringBuffer sb = new StringBuffer();
        sb.append("Blocked attempt to access inaccessible method '");
        sb.append(getSourceRepresentation(serviceMethod));
        sb.append("'");

        if (target != null) {
            sb.append(" on target '");
            sb.append(printTypeName(target.getClass()));
            sb.append("'");
        }

        sb.append("; this is either misconfiguration or a hack attempt");

        return sb.toString();
    }

    private static String printTypeName(Class<?> type) {
        // Primitives
        //
        if (type.equals(Integer.TYPE)) {
            return "int";
        } else if (type.equals(Long.TYPE)) {
            return "long";
        } else if (type.equals(Short.TYPE)) {
            return "short";
        } else if (type.equals(Byte.TYPE)) {
            return "byte";
        } else if (type.equals(Character.TYPE)) {
            return "char";
        } else if (type.equals(Boolean.TYPE)) {
            return "boolean";
        } else if (type.equals(Float.TYPE)) {
            return "float";
        } else if (type.equals(Double.TYPE)) {
            return "double";
        }

        // Arrays
        //
        if (type.isArray()) {
            Class<?> componentType = type.getComponentType();
            return printTypeName(componentType) + "[]";
        }

        // Everything else
        //
        return type.getName().replace('$', '.');
    }

    private static String getSourceRepresentation(Method method) {
        return method.toString().replace('$', '.');
    }

}