/*
* $Id: JSONResult.java 1189257 2011-10-26 15:06:17Z mcucchiara $
*
* 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.struts2.json;
import com.opensymphony.xwork2.ActionContext;
import com.opensymphony.xwork2.ActionInvocation;
import com.opensymphony.xwork2.Result;
import com.opensymphony.xwork2.inject.Inject;
import com.opensymphony.xwork2.util.ValueStack;
import com.opensymphony.xwork2.util.WildcardUtil;
import com.opensymphony.xwork2.util.logging.Logger;
import com.opensymphony.xwork2.util.logging.LoggerFactory;
import org.apache.struts2.StrutsConstants;
import org.apache.struts2.StrutsStatics;
import org.apache.struts2.json.smd.SMDGenerator;
import javax.servlet.http.HttpServletRequest;
import javax.servlet.http.HttpServletResponse;
import java.io.IOException;
import java.util.ArrayList;
import java.util.List;
import java.util.Set;
import java.util.regex.Pattern;
/**
* <!-- START SNIPPET: description --> <p/> This result serializes an action
* into JSON. <p/> <!-- END SNIPPET: description --> <p/> <p/> <u>Result
* parameters:</u> <p/> <!-- START SNIPPET: parameters --> <p/>
* <ul>
* <p/>
* <li>excludeProperties - list of regular expressions matching the properties
* to be excluded. The regular expressions are evaluated against the OGNL
* expression representation of the properties. </li>
* <p/>
* </ul>
* <p/> <!-- END SNIPPET: parameters --> <p/> <b>Example:</b> <p/>
* <p/>
* <pre>
* <!-- START SNIPPET: example -->
* <result name="success" type="json" />
* <!-- END SNIPPET: example -->
* </pre>
*/
public class JSONResult implements Result {
private static final long serialVersionUID = 8624350183189931165L;
private static final Logger LOG = LoggerFactory.getLogger(JSONResult.class);
private String defaultEncoding = "ISO-8859-1";
private List<Pattern> includeProperties;
private List<Pattern> excludeProperties;
private String root;
private boolean wrapWithComments;
private boolean prefix;
private boolean enableSMD = false;
private boolean enableGZIP = false;
private boolean ignoreHierarchy = true;
private boolean ignoreInterfaces = true;
private boolean enumAsBean = JSONWriter.ENUM_AS_BEAN_DEFAULT;
private boolean noCache = false;
private boolean excludeNullProperties = false;
private int statusCode;
private int errorCode;
private String callbackParameter;
private String contentType;
private String wrapPrefix;
private String wrapSuffix;
@Inject(StrutsConstants.STRUTS_I18N_ENCODING)
public void setDefaultEncoding(String val) {
this.defaultEncoding = val;
}
/**
* Gets a list of regular expressions of properties to exclude from the JSON
* output.
*
* @return A list of compiled regular expression patterns
*/
public List<Pattern> getExcludePropertiesList() {
return this.excludeProperties;
}
/**
* Sets a comma-delimited list of regular expressions to match properties
* that should be excluded from the JSON output.
*
* @param commaDelim A comma-delimited list of regular expressions
*/
public void setExcludeProperties(String commaDelim) {
Set<String> excludePatterns = JSONUtil.asSet(commaDelim);
if (excludePatterns != null) {
this.excludeProperties = new ArrayList<Pattern>(excludePatterns.size());
for (String pattern : excludePatterns) {
this.excludeProperties.add(Pattern.compile(pattern));
}
}
}
/**
* Sets a comma-delimited list of wildcard expressions to match properties
* that should be excluded from the JSON output.
*
* @param commaDelim A comma-delimited list of wildcard patterns
*/
public void setExcludeWildcards(String commaDelim) {
Set<String> excludePatterns = JSONUtil.asSet(commaDelim);
if (excludePatterns != null) {
this.excludeProperties = new ArrayList<Pattern>(excludePatterns.size());
for (String pattern : excludePatterns) {
this.excludeProperties.add(WildcardUtil.compileWildcardPattern(pattern));
}
}
}
/**
* @return the includeProperties
*/
public List<Pattern> getIncludePropertiesList() {
return includeProperties;
}
/**
* Sets a comma-delimited list of regular expressions to match properties
* that should be included in the JSON output.
*
* @param commaDelim A comma-delimited list of regular expressions
*/
public void setIncludeProperties(String commaDelim) {
includeProperties = JSONUtil.processIncludePatterns(JSONUtil.asSet(commaDelim), JSONUtil.REGEXP_PATTERN);
}
/**
* Sets a comma-delimited list of wildcard expressions to match properties
* that should be included in the JSON output.
*
* @param commaDelim A comma-delimited list of wildcard patterns
*/
public void setIncludeWildcards(String commaDelim) {
includeProperties = JSONUtil.processIncludePatterns(JSONUtil.asSet(commaDelim), JSONUtil.WILDCARD_PATTERN);
}
public void execute(ActionInvocation invocation) throws Exception {
ActionContext actionContext = invocation.getInvocationContext();
HttpServletRequest request = (HttpServletRequest) actionContext.get(StrutsStatics.HTTP_REQUEST);
HttpServletResponse response = (HttpServletResponse) actionContext.get(StrutsStatics.HTTP_RESPONSE);
try {
Object rootObject;
rootObject = readRootObject(invocation);
writeToResponse(response, createJSONString(request, rootObject), enableGzip(request));
} catch (IOException exception) {
LOG.error(exception.getMessage(), exception);
throw exception;
}
}
private Object readRootObject(ActionInvocation invocation) {
if (enableSMD) {
return buildSMDObject(invocation);
}
return findRootObject(invocation);
}
private Object findRootObject(ActionInvocation invocation) {
Object rootObject;
if (this.root != null) {
ValueStack stack = invocation.getStack();
rootObject = stack.findValue(root);
} else {
rootObject = invocation.getStack().peek(); // model overrides action
}
return rootObject;
}
private String createJSONString(HttpServletRequest request, Object rootObject) throws JSONException {
String json;
json = JSONUtil.serialize(rootObject, excludeProperties, includeProperties, ignoreHierarchy,
enumAsBean, excludeNullProperties);
json = addCallbackIfApplicable(request, json);
return json;
}
private boolean enableGzip(HttpServletRequest request) {
return enableGZIP && JSONUtil.isGzipInRequest(request);
}
protected void writeToResponse(HttpServletResponse response, String json, boolean gzip) throws IOException {
JSONUtil.writeJSONToResponse(new SerializationParams(response, getEncoding(), isWrapWithComments(),
json, false, gzip, noCache, statusCode, errorCode, prefix, contentType, wrapPrefix,
wrapSuffix));
}
@SuppressWarnings("unchecked")
protected org.apache.struts2.json.smd.SMD buildSMDObject(ActionInvocation invocation) {
return new SMDGenerator(findRootObject(invocation), excludeProperties, ignoreInterfaces).generate(invocation);
}
/**
* Retrieve the encoding <p/>
*
* @return The encoding associated with this template (defaults to the value
* of 'struts.i18n.encoding' property)
*/
protected String getEncoding() {
String encoding = this.defaultEncoding;
if (encoding == null) {
encoding = System.getProperty("file.encoding");
}
if (encoding == null) {
encoding = "UTF-8";
}
return encoding;
}
protected String addCallbackIfApplicable(HttpServletRequest request, String json) {
if ((callbackParameter != null) && (callbackParameter.length() > 0)) {
String callbackName = request.getParameter(callbackParameter);
if ((callbackName != null) && (callbackName.length() > 0))
json = callbackName + "(" + json + ")";
}
return json;
}
/**
* @return OGNL expression of root object to be serialized
*/
public String getRoot() {
return this.root;
}
/**
* Sets the root object to be serialized, defaults to the Action
*
* @param root OGNL expression of root object to be serialized
*/
public void setRoot(String root) {
this.root = root;
}
/**
* @return Generated JSON must be enclosed in comments
*/
public boolean isWrapWithComments() {
return this.wrapWithComments;
}
/**
* Wrap generated JSON with comments
*
* @param wrapWithComments
*/
public void setWrapWithComments(boolean wrapWithComments) {
this.wrapWithComments = wrapWithComments;
}
/**
* @return Result has SMD generation enabled
*/
public boolean isEnableSMD() {
return this.enableSMD;
}
/**
* Enable SMD generation for action, which can be used for JSON-RPC
*
* @param enableSMD
*/
public void setEnableSMD(boolean enableSMD) {
this.enableSMD = enableSMD;
}
public void setIgnoreHierarchy(boolean ignoreHierarchy) {
this.ignoreHierarchy = ignoreHierarchy;
}
/**
* Controls whether interfaces should be inspected for method annotations
* You may need to set to this true if your action is a proxy as annotations
* on methods are not inherited
*/
public void setIgnoreInterfaces(boolean ignoreInterfaces) {
this.ignoreInterfaces = ignoreInterfaces;
}
/**
* Controls how Enum's are serialized : If true, an Enum is serialized as a
* name=value pair (name=name()) (default) If false, an Enum is serialized
* as a bean with a special property _name=name()
*
* @param enumAsBean
*/
public void setEnumAsBean(boolean enumAsBean) {
this.enumAsBean = enumAsBean;
}
public boolean isEnumAsBean() {
return enumAsBean;
}
public boolean isEnableGZIP() {
return enableGZIP;
}
public void setEnableGZIP(boolean enableGZIP) {
this.enableGZIP = enableGZIP;
}
public boolean isNoCache() {
return noCache;
}
/**
* Add headers to response to prevent the browser from caching the response
*
* @param noCache
*/
public void setNoCache(boolean noCache) {
this.noCache = noCache;
}
public boolean isIgnoreHierarchy() {
return ignoreHierarchy;
}
public boolean isExcludeNullProperties() {
return excludeNullProperties;
}
/**
* Do not serialize properties with a null value
*
* @param excludeNullProperties
*/
public void setExcludeNullProperties(boolean excludeNullProperties) {
this.excludeNullProperties = excludeNullProperties;
}
/**
* Status code to be set in the response
*
* @param statusCode
*/
public void setStatusCode(int statusCode) {
this.statusCode = statusCode;
}
/**
* Error code to be set in the response
*
* @param errorCode
*/
public void setErrorCode(int errorCode) {
this.errorCode = errorCode;
}
public void setCallbackParameter(String callbackParameter) {
this.callbackParameter = callbackParameter;
}
public String getCallbackParameter() {
return callbackParameter;
}
/**
* Prefix JSON with "{} &&"
*
* @param prefix
*/
public void setPrefix(boolean prefix) {
this.prefix = prefix;
}
/**
* Content type to be set in the response
*
* @param contentType
*/
public void setContentType(String contentType) {
this.contentType = contentType;
}
public String getWrapPrefix() {
return wrapPrefix;
}
/**
* Text to be inserted at the begining of the response
*/
public void setWrapPrefix(String wrapPrefix) {
this.wrapPrefix = wrapPrefix;
}
public String getWrapSuffix() {
return wrapSuffix;
}
/**
* Text to be inserted at the end of the response
*/
public void setWrapSuffix(String wrapSuffix) {
this.wrapSuffix = wrapSuffix;
}
}