com.almende.eve.rpc.jsonrpc.JSONResponse.java Source code

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Here is the source code for com.almende.eve.rpc.jsonrpc.JSONResponse.java

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/*
 * Copyright: Almende B.V. (2014), Rotterdam, The Netherlands
 * License: The Apache Software License, Version 2.0
 */
package com.almende.eve.rpc.jsonrpc;

import java.io.IOException;
import java.util.logging.Level;
import java.util.logging.Logger;

import com.almende.eve.rpc.jsonrpc.jackson.JOM;
import com.fasterxml.jackson.core.JsonParseException;
import com.fasterxml.jackson.databind.JsonNode;
import com.fasterxml.jackson.databind.ObjectMapper;
import com.fasterxml.jackson.databind.node.ObjectNode;

/**
 * The Class JSONResponse.
 */
public final class JSONResponse extends JSONMessage {
    private static final long serialVersionUID = 12392962249054051L;
    private final ObjectNode resp = JOM.createObjectNode();
    private static final Logger LOG = Logger.getLogger(JSONResponse.class.getName());

    /**
     * Instantiates a new jSON response.
     */
    public JSONResponse() {
        init(null, null, null);
    }

    /**
     * Instantiates a new jSON response.
     *
     * @param json the json
     * @throws JSONRPCException the jSONRPC exception
     * @throws IOException Signals that an I/O exception has occurred.
     */
    public JSONResponse(final String json) throws JSONRPCException, IOException {
        final ObjectMapper mapper = JOM.getInstance();
        try {
            init(mapper.readValue(json, ObjectNode.class));
        } catch (final JsonParseException e) {
            LOG.warning("Failed to parse JSON: '" + json + "'");
            throw e;
        }
    }

    /**
     * Instantiates a new jSON response.
     *
     * @param response the response
     * @throws JSONRPCException the jSONRPC exception
     */
    public JSONResponse(final ObjectNode response) throws JSONRPCException {
        init(response);
    }

    /**
     * Instantiates a new jSON response.
     *
     * @param result the result
     */
    public JSONResponse(final Object result) {
        init(null, result, null);
    }

    /**
     * Instantiates a new jSON response.
     *
     * @param id the id
     * @param result the result
     */
    public JSONResponse(final JsonNode id, final Object result) {
        init(id, result, null);
    }

    /**
     * Instantiates a new jSON response.
     *
     * @param error the error
     */
    public JSONResponse(final JSONRPCException error) {
        init(null, null, error);
    }

    /**
     * Instantiates a new jSON response.
     *
     * @param id the id
     * @param error the error
     */
    public JSONResponse(final JsonNode id, final JSONRPCException error) {
        init(id, null, error);
    }

    /**
     * Inits the.
     *
     * @param response the response
     * @throws JSONRPCException the jSONRPC exception
     */
    private void init(final ObjectNode response) throws JSONRPCException {
        if (response == null || response.isNull()) {
            throw new JSONRPCException(JSONRPCException.CODE.INVALID_REQUEST, "Response is null");
        }
        if (response.has(JSONRPC) && response.get(JSONRPC).isTextual()
                && !response.get(JSONRPC).asText().equals(VERSION)) {
            throw new JSONRPCException(JSONRPCException.CODE.INVALID_REQUEST,
                    "Value of member 'jsonrpc' must be '2.0'");
        }
        final boolean hasError = response.has(ERROR) && !response.get(ERROR).isNull();
        if (hasError && !(response.get(ERROR).isObject())) {
            throw new JSONRPCException(JSONRPCException.CODE.INVALID_REQUEST, "Member 'error' is no ObjectNode");
        }

        final JsonNode id = response.get(ID);
        final Object result = response.get(RESULT);
        JSONRPCException error = null;
        if (hasError) {
            error = new JSONRPCException((ObjectNode) response.get(ERROR));
        }

        init(id, result, error);
    }

    /**
     * Inits the.
     *
     * @param id the id
     * @param result the result
     * @param error the error
     */
    private void init(final JsonNode id, final Object result, final JSONRPCException error) {
        setVersion();
        setId(id);
        setResult(result);
        setError(error);
    }

    /**
     * Sets the id.
     *
     * @param id the new id
     */
    public void setId(final JsonNode id) {
        resp.put(ID, id);
    }

    /* (non-Javadoc)
     * @see com.almende.eve.rpc.jsonrpc.JSONMessage#getId()
     */
    @Override
    public JsonNode getId() {
        return resp.get(ID);
    }

    /**
     * Sets the result.
     *
     * @param result the new result
     */
    public void setResult(final Object result) {
        if (result != null) {
            final ObjectMapper mapper = JOM.getInstance();
            resp.put(RESULT, mapper.convertValue(result, JsonNode.class));
            setError(null);
        } else {
            if (resp.has(RESULT)) {
                resp.remove(RESULT);
            }
        }
    }

    /**
     * Gets the result.
     *
     * @return the result
     */
    public JsonNode getResult() {
        return resp.get(RESULT);
    }

    /**
     * Sets the error.
     *
     * @param error the new error
     */
    public void setError(final JSONRPCException error) {
        if (error != null) {
            resp.put(ERROR, error.getObjectNode());
            setResult(null);
        } else {
            if (resp.has(ERROR)) {
                resp.remove(ERROR);
            }
        }
    }

    /**
     * Gets the error.
     *
     * @return the error
     */
    public JSONRPCException getError() {
        if (resp.has(ERROR)) {
            final ObjectNode error = (ObjectNode) resp.get(ERROR);
            return new JSONRPCException(error);
        } else {
            return null;
        }
    }

    /**
     * Sets the version.
     */
    private void setVersion() {
        resp.put(JSONRPC, VERSION);
    }

    /**
     * Gets the object node.
     *
     * @return the object node
     */
    public ObjectNode getObjectNode() {
        return resp;
    }

    /* (non-Javadoc)
     * @see java.lang.Object#toString()
     */
    @Override
    public String toString() {
        final ObjectMapper mapper = JOM.getInstance();
        try {
            return mapper.writeValueAsString(resp);
        } catch (final Exception e) {
            LOG.log(Level.SEVERE, "Failed to stringify response.", e);
        }
        return null;
    }
}