RM-1641 (Create Relationship Service)

* Added a new utility class to reduce boilerplate code

git-svn-id: https://svn.alfresco.com/repos/alfresco-enterprise/modules/recordsmanagement/HEAD@85481 c4b6b30b-aa2e-2d43-bbcb-ca4b014f7261

rm-server/source/java/org/alfresco/module/org_alfresco_module_rm/script/AbstractRmWebScript.java

@@ -18,9 +18,8 @@
  */
 package org.alfresco.module.org_alfresco_module_rm.script;
 
-import java.io.IOException;
-import java.io.Serializable;
-import java.util.List;
+import static org.alfresco.util.WebScriptUtils.getTemplateVars;
+
 import java.util.Map;
 
 import javax.servlet.http.HttpServletResponse;
@@ -29,13 +28,7 @@ import org.alfresco.module.org_alfresco_module_rm.disposition.DispositionService
 import org.alfresco.service.cmr.repository.NodeRef;
 import org.alfresco.service.cmr.repository.NodeService;
 import org.alfresco.service.namespace.NamespaceService;
-import org.apache.commons.lang3.StringUtils;
-import org.json.JSONException;
-import org.json.JSONObject;
-import org.json.JSONTokener;
-import org.springframework.extensions.surf.util.Content;
 import org.springframework.extensions.webscripts.DeclarativeWebScript;
-import org.springframework.extensions.webscripts.Status;
 import org.springframework.extensions.webscripts.WebScriptException;
 import org.springframework.extensions.webscripts.WebScriptRequest;
 
@@ -118,151 +111,4 @@ public abstract class AbstractRmWebScript extends DeclarativeWebScript
 
         return nodeRef;
     }
-
-    /**
-     * This method checks if the json object contains an entry with the specified name.
-     *
-     * @param json the json object.
-     * @param paramName the name to check for.
-     * @throws WebScriptException if the specified entry is missing.
-     */
-    protected void checkMandatoryJsonParam(JSONObject json, String paramName)
-    {
-        if (!json.has(paramName))
-        {
-            throw new WebScriptException(Status.STATUS_BAD_REQUEST,
-                    "Mandatory '" + paramName + "' parameter was not provided in request body");
-        }
-    }
-
-    /**
-     * This method checks if the json object contains entries with the specified names.
-     *
-     * @param json the json object.
-     * @param paramNames the names to check for.
-     * @throws WebScriptException if any of the specified entries are missing.
-     */
-    protected void checkMandatoryJsonParams(JSONObject json, List<String> paramNames)
-    {
-        for (String name : paramNames)
-        {
-            checkMandatoryJsonParam(json, name);
-        }
-    }
-
-    /**
-     * Gets the template variable substitutions map
-     *
-     * @param req The webscript request
-     * @return The template variable substitutions
-     */
-    protected Map<String, String> getTemplateVars(WebScriptRequest req)
-    {
-        if (req == null)
-        {
-            throw new WebScriptException(Status.STATUS_BAD_REQUEST, "The webscript request is null.");
-        }
-
-        if (req.getServiceMatch() == null)
-        {
-            throw new WebScriptException(Status.STATUS_BAD_REQUEST, "The matching API Service for the request is null.");
-        }
-
-        Map<String, String> templateVars = req.getServiceMatch().getTemplateVars();
-        if (templateVars == null)
-        {
-            throw new WebScriptException(Status.STATUS_BAD_REQUEST, "The template variable substitutions map is null");
-        }
-
-        return templateVars;
-    }
-
-    /**
-     * Gets the value of a request parameter
-     *
-     * @param req The webscript request
-     * @param parameter The request parameter
-     * @return The value of the request parameter
-     */
-    protected String getRequestParameterValue(WebScriptRequest req, String parameter)
-    {
-        Map<String, String> templateVars = getTemplateVars(req);
-        return templateVars.get(parameter);
-    }
-
-    /**
-     * Gets the request content as JSON object
-     *
-     * @param req The webscript request
-     * @return The request content as JSON object
-     */
-    protected JSONObject getRequestContentAsJsonObject(WebScriptRequest req)
-    {
-        Content reqContent = req.getContent();
-        if (reqContent == null)
-        {
-            throw new WebScriptException(Status.STATUS_BAD_REQUEST, "Missing request body.");
-        }
-
-        String content;
-        try
-        {
-            content = reqContent.getContent();
-        }
-        catch (IOException error)
-        {
-            throw new WebScriptException(Status.STATUS_BAD_REQUEST, "Could not get conent from the request.", error);
-        }
-
-        if (StringUtils.isBlank(content))
-        {
-            throw new WebScriptException(Status.STATUS_BAD_REQUEST, "Content does not exist.");
-        }
-
-        JSONTokener jsonTokener;
-        try
-        {
-            jsonTokener = new JSONTokener(req.getContent().getContent());
-        }
-        catch (IOException error)
-        {
-            throw new WebScriptException(Status.STATUS_BAD_REQUEST, "Could not get content.", error);
-        }
-
-        JSONObject json;
-        try
-        {
-            json = new JSONObject(jsonTokener);
-        }
-        catch (JSONException error)
-        {
-            throw new WebScriptException(Status.STATUS_BAD_REQUEST, "Unable to parse request body.", error);
-        }
-
-        return json;
-    }
-
-    /**
-     * Gets the value of a given key from a json object
-     *
-     * @param jsonObject The json object from which the value should be retrieved
-     * @param key The key for which the value is requested
-     * @return The value of the given key from the json object
-     */
-    protected Serializable getJSONObjectValue(JSONObject jsonObject, String key)
-    {
-        Serializable value;
-
-        try
-        {
-            checkMandatoryJsonParam(jsonObject, key);
-            value = (Serializable) jsonObject.get(key);
-        }
-        catch (JSONException error)
-        {
-            throw new WebScriptException(Status.STATUS_BAD_REQUEST, "Could not get value for the key '" + key + "'.", error);
-        }
-
-        return value;
-    }
 }

rm-server/source/java/org/alfresco/module/org_alfresco_module_rm/script/CustomReferenceDefinitionBase.java

@@ -18,14 +18,13 @@
  */
 package org.alfresco.module.org_alfresco_module_rm.script;
 
+import static org.alfresco.util.WebScriptUtils.getStringValueFromJSONObject;
+
 import org.alfresco.module.org_alfresco_module_rm.admin.RecordsManagementAdminService;
-import org.alfresco.service.cmr.dictionary.DictionaryService;
 import org.alfresco.service.namespace.QName;
-import org.apache.commons.lang.StringUtils;
 import org.json.JSONObject;
 import org.springframework.extensions.webscripts.Status;
 import org.springframework.extensions.webscripts.WebScriptException;
-import org.springframework.extensions.webscripts.WebScriptRequest;
 
 /**
  * Base class for custom reference definition classes
@@ -48,9 +47,6 @@ public class CustomReferenceDefinitionBase extends AbstractRmWebScript
     /** Records Management Admin Service */
     private RecordsManagementAdminService rmAdminService;
 
-    /** Dictionary Service */
-    private DictionaryService dictionaryService;
-
     /**
      * Sets the records management admin service
      *
@@ -71,26 +67,6 @@ public class CustomReferenceDefinitionBase extends AbstractRmWebScript
         return this.rmAdminService;
     }
 
-    /**
-     * Sets the dictionary service
-     *
-     * @param dictionaryService The dictionary service
-     */
-    public void setDictionaryService(DictionaryService dictionaryService)
-    {
-        this.dictionaryService = dictionaryService;
-    }
-
-    /**
-     * Gets the dictionary service instance
-     *
-     * @return The dictionary service instance
-     */
-    protected DictionaryService getDictionaryService()
-    {
-        return this.dictionaryService;
-    }
-
     /**
      * Gets the QName for the given custom reference id
      *
@@ -121,22 +97,7 @@ public class CustomReferenceDefinitionBase extends AbstractRmWebScript
      */
     protected CustomReferenceType getCustomReferenceType(JSONObject requestContent)
     {
-        String referenceType = (String) getJSONObjectValue(requestContent, REFERENCE_TYPE);
-        if (StringUtils.isBlank(referenceType))
-        {
-            throw new WebScriptException(Status.STATUS_BAD_REQUEST, "Reference type is missing.");
-        }
+        String referenceType = getStringValueFromJSONObject(requestContent, REFERENCE_TYPE);
         return CustomReferenceType.getEnumFromString(referenceType);
     }
-
-    /**
-     * Gets the service path from the webscript request
-     *
-     * @param req The webscript request
-     * @return The service path
-     */
-    protected String getServicePath(WebScriptRequest req)
-    {
-        return req.getServicePath();
-    }
 }

rm-server/source/java/org/alfresco/module/org_alfresco_module_rm/script/CustomReferenceDefinitionPost.java

@@ -18,11 +18,13 @@
  */
 package org.alfresco.module.org_alfresco_module_rm.script;
 
+import static org.alfresco.util.WebScriptUtils.getRequestContentAsJsonObject;
+import static org.alfresco.util.WebScriptUtils.getStringValueFromJSONObject;
+
 import java.util.HashMap;
 import java.util.Map;
 
 import org.alfresco.service.namespace.QName;
-import org.apache.commons.lang.StringUtils;
 import org.json.JSONObject;
 import org.springframework.extensions.webscripts.Cache;
 import org.springframework.extensions.webscripts.Status;
@@ -49,7 +51,7 @@ public class CustomReferenceDefinitionPost extends CustomReferenceDefinitionBase
         QName customReference = addCustomReference(requestContent, customReferenceType);
 
         Map<String, Object> model = new HashMap<String, Object>();
-        String servicePath = getServicePath(req);
+        String servicePath = req.getServicePath();
         Map<String, Object> customReferenceData = getCustomReferenceData(customReferenceType, customReference, servicePath);
         model.putAll(customReferenceData);
 
@@ -69,28 +71,13 @@ public class CustomReferenceDefinitionPost extends CustomReferenceDefinitionBase
 
         if (CustomReferenceType.PARENT_CHILD.equals(customReferenceType))
         {
-            String source = (String) getJSONObjectValue(requestContent, SOURCE);
-            if (StringUtils.isBlank(source))
-            {
-                throw new WebScriptException(Status.STATUS_BAD_REQUEST, "Source is blank.");
-            }
-
-            String target = (String) getJSONObjectValue(requestContent, TARGET);
-            if (StringUtils.isBlank(target))
-            {
-                throw new WebScriptException(Status.STATUS_BAD_REQUEST, "Target is blank.");
-            }
-
+            String source = getStringValueFromJSONObject(requestContent, SOURCE);
+            String target = getStringValueFromJSONObject(requestContent, TARGET);
             referenceQName = getRmAdminService().addCustomChildAssocDefinition(source, target);
         }
         else if (CustomReferenceType.BIDIRECTIONAL.equals(customReferenceType))
         {
-            String label = (String) getJSONObjectValue(requestContent, LABEL);
-            if (StringUtils.isBlank(label))
-            {
-                throw new WebScriptException(Status.STATUS_BAD_REQUEST, "Label is blank.");
-            }
-
+            String label = getStringValueFromJSONObject(requestContent, LABEL);
             referenceQName = getRmAdminService().addCustomAssocDefinition(label);
         }
         else

rm-server/source/java/org/alfresco/module/org_alfresco_module_rm/script/CustomReferenceDefinitionPut.java

@@ -18,11 +18,14 @@
  */
 package org.alfresco.module.org_alfresco_module_rm.script;
 
+import static org.alfresco.util.WebScriptUtils.getRequestContentAsJsonObject;
+import static org.alfresco.util.WebScriptUtils.getRequestParameterValue;
+import static org.alfresco.util.WebScriptUtils.getStringValueFromJSONObject;
+
 import java.util.HashMap;
 import java.util.Map;
 
 import org.alfresco.service.namespace.QName;
-import org.apache.commons.lang.StringUtils;
 import org.json.JSONObject;
 import org.springframework.extensions.webscripts.Cache;
 import org.springframework.extensions.webscripts.Status;
@@ -46,33 +49,17 @@ public class CustomReferenceDefinitionPut extends CustomReferenceDefinitionBase
     protected Map<String, Object> executeImpl(WebScriptRequest req, Status status, Cache cache)
     {
         JSONObject requestContent = getRequestContentAsJsonObject(req);
-        String referenceId = getReferenceId(req);
+        String referenceId = getRequestParameterValue(req, REF_ID);
         updateCustomReference(requestContent, referenceId);
 
         Map<String, Object> model = new HashMap<String, Object>();
-        String servicePath = getServicePath(req);
+        String servicePath = req.getServicePath();
         Map<String, Object> customReferenceData = getCustomReferenceData(servicePath, referenceId);
         model.putAll(customReferenceData);
 
         return model;
     }
 
-    /**
-     * Gets the reference id from the webscript request
-     *
-     * @param req The webscript request
-     * @return The reference id
-     */
-    private String getReferenceId(WebScriptRequest req)
-    {
-        String referenceId = getRequestParameterValue(req, REF_ID);
-        if (StringUtils.isBlank(referenceId))
-        {
-            throw new WebScriptException(Status.STATUS_NOT_FOUND, "Reference id is blank.");
-        }
-        return referenceId;
-    }
-
     /**
      * Updates the custom reference
      *
@@ -86,28 +73,13 @@ public class CustomReferenceDefinitionPut extends CustomReferenceDefinitionBase
 
         if (CustomReferenceType.PARENT_CHILD.equals(customReferenceType))
         {
-            String source = (String) getJSONObjectValue(requestContent, SOURCE);
-            if (StringUtils.isBlank(source))
-            {
-                throw new WebScriptException(Status.STATUS_BAD_REQUEST, "Source is blank.");
-            }
-
-            String target = (String) getJSONObjectValue(requestContent, TARGET);
-            if (StringUtils.isBlank(target))
-            {
-                throw new WebScriptException(Status.STATUS_BAD_REQUEST, "Target is blank.");
-            }
-
+            String source = getStringValueFromJSONObject(requestContent, SOURCE);
+            String target = getStringValueFromJSONObject(requestContent, TARGET);
             getRmAdminService().updateCustomChildAssocDefinition(referenceQName, source, target);
         }
         else if (CustomReferenceType.BIDIRECTIONAL.equals(customReferenceType))
         {
-            String label = (String) getJSONObjectValue(requestContent, LABEL);
-            if (StringUtils.isBlank(label))
-            {
-                throw new WebScriptException(Status.STATUS_BAD_REQUEST, "Label is blank.");
-            }
-
+            String label = getStringValueFromJSONObject(requestContent, LABEL);
             getRmAdminService().updateCustomAssocDefinition(referenceQName, label);
         }
         else

rm-server/source/java/org/alfresco/module/org_alfresco_module_rm/script/CustomReferenceDefinitionsGet.java

@@ -18,6 +18,8 @@
  */
 package org.alfresco.module.org_alfresco_module_rm.script;
 
+import static org.alfresco.util.WebScriptUtils.getRequestParameterValue;
+
 import java.util.ArrayList;
 import java.util.HashMap;
 import java.util.List;
@@ -26,6 +28,7 @@ import java.util.Map.Entry;
 
 import org.alfresco.service.cmr.dictionary.AssociationDefinition;
 import org.alfresco.service.cmr.dictionary.ChildAssociationDefinition;
+import org.alfresco.service.cmr.dictionary.DictionaryService;
 import org.alfresco.service.namespace.QName;
 import org.apache.commons.lang.StringUtils;
 import org.springframework.extensions.webscripts.Cache;
@@ -41,13 +44,36 @@ import org.springframework.extensions.webscripts.WebScriptRequest;
  */
 public class CustomReferenceDefinitionsGet extends CustomReferenceDefinitionBase
 {
+    /** Dictionary Service */
+    private DictionaryService dictionaryService;
+
+    /**
+     * Sets the dictionary service
+     *
+     * @param dictionaryService The dictionary service
+     */
+    public void setDictionaryService(DictionaryService dictionaryService)
+    {
+        this.dictionaryService = dictionaryService;
+    }
+
+    /**
+     * Gets the dictionary service instance
+     *
+     * @return The dictionary service instance
+     */
+    protected DictionaryService getDictionaryService()
+    {
+        return this.dictionaryService;
+    }
+
     /**
      * @see org.springframework.extensions.webscripts.DeclarativeWebScript#executeImpl(org.springframework.extensions.webscripts.WebScriptRequest, org.springframework.extensions.webscripts.Status, org.springframework.extensions.webscripts.Cache)
      */
     @Override
     protected Map<String, Object> executeImpl(WebScriptRequest req, Status status, Cache cache)
     {
-        String referenceId = getRequestParameterValue(req, REF_ID);
+        String referenceId = getRequestParameterValue(req, REF_ID, false);
         Map<QName, AssociationDefinition> customReferenceDefinitions = getCustomReferenceDefinitions(referenceId);
         List<Map<String, String>> customReferenceData = getCustomReferenceData(customReferenceDefinitions);
 

rm-server/source/java/org/alfresco/module/org_alfresco_module_rm/script/slingshot/RecordedVersionConfigPost.java

@@ -18,7 +18,9 @@
  */
 package org.alfresco.module.org_alfresco_module_rm.script.slingshot;
 
-import java.io.IOException;
+import static org.alfresco.util.WebScriptUtils.getRequestContentAsJsonObject;
+import static org.alfresco.util.WebScriptUtils.getStringValueFromJSONObject;
+
 import java.util.HashMap;
 import java.util.Map;
 
@@ -26,12 +28,9 @@ import org.alfresco.module.org_alfresco_module_rm.script.AbstractRmWebScript;
 import org.alfresco.module.org_alfresco_module_rm.version.RecordableVersionModel;
 import org.alfresco.module.org_alfresco_module_rm.version.RecordableVersionPolicy;
 import org.alfresco.service.cmr.repository.NodeRef;
-import org.json.JSONException;
 import org.json.JSONObject;
-import org.json.JSONTokener;
 import org.springframework.extensions.webscripts.Cache;
 import org.springframework.extensions.webscripts.Status;
-import org.springframework.extensions.webscripts.WebScriptException;
 import org.springframework.extensions.webscripts.WebScriptRequest;
 
 /**
@@ -65,30 +64,8 @@ public class RecordedVersionConfigPost extends AbstractRmWebScript implements Re
      */
     private RecordableVersionPolicy getRecordableVersionPolicy(WebScriptRequest req)
     {
-        String recordedVersion = getRecordedVersion(req);
+        JSONObject requestContent = getRequestContentAsJsonObject(req);
+        String recordedVersion = getStringValueFromJSONObject(requestContent, RECORDED_VERSION);
         return RecordableVersionPolicy.valueOf(recordedVersion);
     }
-
-    /**
-     * Gets the recorded version parameter value from the request
-     *
-     * @param req The webscript request
-     * @return The recorded version parameter value
-     */
-    private String getRecordedVersion(WebScriptRequest req)
-    {
-        try
-        {
-            // Convert the request content to JSON
-            String content = req.getContent().getContent();
-            JSONObject jsonObject = new JSONObject(new JSONTokener(content));
-            checkMandatoryJsonParam(jsonObject, RECORDED_VERSION);
-            return jsonObject.getString(RECORDED_VERSION);
-        }
-        catch (JSONException | IOException ex)
-        {
-            throw new WebScriptException(Status.STATUS_BAD_REQUEST,
-                    "Could not parse JSON from req.", ex);
-        }
-    }
 }

rm-server/source/java/org/alfresco/util/WebScriptUtils.java

@@ -0,0 +1,295 @@
+/*
+ * Copyright (C) 2005-2014 Alfresco Software Limited.
+ *
+ * This file is part of Alfresco
+ *
+ * Alfresco is free software: you can redistribute it and/or modify
+ * it under the terms of the GNU Lesser General Public License as published by
+ * the Free Software Foundation, either version 3 of the License, or
+ * (at your option) any later version.
+ *
+ * Alfresco is distributed in the hope that it will be useful,
+ * but WITHOUT ANY WARRANTY; without even the implied warranty of
+ * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
+ * GNU Lesser General Public License for more details.
+ *
+ * You should have received a copy of the GNU Lesser General Public License
+ * along with Alfresco. If not, see <http://www.gnu.org/licenses/>.
+ */
+package org.alfresco.util;
+
+import static org.alfresco.util.ParameterCheck.mandatory;
+import static org.alfresco.util.ParameterCheck.mandatoryString;
+import static org.apache.commons.lang.StringUtils.isBlank;
+import static org.apache.commons.lang3.StringUtils.isBlank;
+
+import java.io.IOException;
+import java.util.List;
+import java.util.Map;
+
+import org.apache.commons.lang3.StringUtils;
+import org.json.JSONArray;
+import org.json.JSONException;
+import org.json.JSONObject;
+import org.json.JSONTokener;
+import org.springframework.extensions.surf.util.Content;
+import org.springframework.extensions.webscripts.Status;
+import org.springframework.extensions.webscripts.WebScriptException;
+import org.springframework.extensions.webscripts.WebScriptRequest;
+
+/**
+ * Utility class for handling webscript requests
+ *
+ * @author Tuna Aksoy
+ * @since 2.3
+ */
+public final class WebScriptUtils
+{
+    private WebScriptUtils()
+    {
+        // Will not be called
+    }
+
+    /**
+     * Gets the template variable substitutions map
+     *
+     * @param req The webscript request
+     * @return The template variable substitutions
+     */
+    public static Map<String, String> getTemplateVars(WebScriptRequest req)
+    {
+        mandatory("req", req);
+
+        if (req.getServiceMatch() == null)
+        {
+            throw new WebScriptException(Status.STATUS_BAD_REQUEST, "The matching API Service for the request is null.");
+        }
+
+        Map<String, String> templateVars = req.getServiceMatch().getTemplateVars();
+        if (templateVars == null)
+        {
+            throw new WebScriptException(Status.STATUS_BAD_REQUEST, "The template variable substitutions map is null");
+        }
+
+        return templateVars;
+    }
+
+    /**
+     * Gets the value of a request parameter
+     *
+     * @param req The webscript request
+     * @param parameter The request parameter
+     * @return The value of the request parameter
+     */
+    public static String getRequestParameterValue(WebScriptRequest req, String parameter)
+    {
+        mandatory("req", req);
+        mandatoryString("parameter", parameter);
+
+        return getRequestParameterValue(req, parameter, true);
+    }
+
+    /**
+     * Gets the value of a request parameter
+     *
+     * @param req The webscript request
+     * @param parameter The request parameter
+     * @param checkValue FIXME!!!
+     * @return The value of the request parameter
+     */
+    public static String getRequestParameterValue(WebScriptRequest req, String parameter, boolean checkValue)
+    {
+        mandatory("req", req);
+        mandatoryString("parameter", parameter);
+
+        Map<String, String> templateVars = getTemplateVars(req);
+        String value = templateVars.get(parameter);
+
+        if (checkValue && isBlank(value))
+        {
+            throw new WebScriptException(Status.STATUS_NOT_FOUND, "The value for the parameter '" + parameter + "' is blank.");
+        }
+
+        return value;
+    }
+
+    /**
+     * Gets the request content as JSON object
+     *
+     * @param req The webscript request
+     * @return The request content as JSON object
+     */
+    public static JSONObject getRequestContentAsJsonObject(WebScriptRequest req)
+    {
+        mandatory("req", req);
+
+        Content reqContent = req.getContent();
+        if (reqContent == null)
+        {
+            throw new WebScriptException(Status.STATUS_BAD_REQUEST, "Missing request body.");
+        }
+
+        String content;
+        try
+        {
+            content = reqContent.getContent();
+        }
+        catch (IOException error)
+        {
+            throw new WebScriptException(Status.STATUS_BAD_REQUEST, "Could not get content from the request.", error);
+        }
+
+        if (StringUtils.isBlank(content))
+        {
+            throw new WebScriptException(Status.STATUS_BAD_REQUEST, "Content does not exist.");
+        }
+
+        JSONTokener jsonTokener = new JSONTokener(content);
+
+        JSONObject json;
+        try
+        {
+            json = new JSONObject(jsonTokener);
+        }
+        catch (JSONException error)
+        {
+            throw new WebScriptException(Status.STATUS_BAD_REQUEST, "Unable to parse request body.", error);
+        }
+
+        return json;
+    }
+
+    /**
+     * Checks if the json object contains an entry with the specified parameter name
+     *
+     * @param jsonObject The json object
+     * @param paramName The parameter name to check for
+     */
+    public static void checkMandatoryJsonParam(JSONObject jsonObject, String paramName)
+    {
+        mandatory("jsonObject", jsonObject);
+        mandatoryString("paramName", paramName);
+
+        if (!jsonObject.has(paramName))
+        {
+            throw new WebScriptException(Status.STATUS_BAD_REQUEST, "The json object does not contain en entry with parameter '" + paramName + "'.");
+        }
+    }
+
+    /**
+     * Checks if the json object contains entries with the specified parameter names
+     *
+     * @param jsonObject The json object.
+     * @param paramNames The parameter names to check for
+     */
+    public static void checkMandatoryJsonParams(JSONObject jsonObject, List<String> paramNames)
+    {
+        mandatory("jsonObject", jsonObject);
+        mandatory("paramNames", paramNames);
+
+        for (String name : paramNames)
+        {
+            checkMandatoryJsonParam(jsonObject, name);
+        }
+    }
+
+    /**
+     * Gets the {@link String} value of a given key from a json object
+     *
+     * @param jsonObject The json object
+     * @param key The key
+     * @return The {@link String} value of the given key from the json object
+     */
+    public static String getStringValueFromJSONObject(JSONObject jsonObject, String key)
+    {
+        mandatory("jsonObject", jsonObject);
+        mandatoryString("key", key);
+
+        return getStringValueFromJSONObject(jsonObject, key, true, true);
+    }
+
+    /**
+     * Gets the {@link String} value of a given key from a json object
+     *
+     * @param jsonObject The json object
+     * @param key The key
+     * @param checkKey Determines if the existence of the key should be checked
+     * @param checkValue Determines if the value should be checked if it is blank or not
+     * @return The {@link String} value of the given key from the json object
+     */
+    public static String getStringValueFromJSONObject(JSONObject jsonObject, String key, boolean checkKey, boolean checkValue)
+    {
+        mandatory("jsonObject", jsonObject);
+        mandatoryString("key", key);
+
+        if (checkKey)
+        {
+            checkMandatoryJsonParam(jsonObject, key);
+        }
+
+        String value;
+
+        try
+        {
+            value = jsonObject.getString(key);
+            if (checkValue && isBlank(value))
+            {
+                throw new WebScriptException(Status.STATUS_BAD_REQUEST, "The vale is missing for the key '" + key + "'.");
+            }
+        }
+        catch (JSONException error)
+        {
+            throw new WebScriptException(Status.STATUS_BAD_REQUEST, "Could not get value for the key '" + key + "'.", error);
+        }
+
+        return value;
+    }
+
+    /**
+     * Puts the given key and value to the json object
+     *
+     * @param jsonObject The json object
+     * @param key The key
+     * @param value The value
+     */
+    public static void putValuetoJSONObject(JSONObject jsonObject, String key, Object value)
+    {
+        mandatory("jsonObject", jsonObject);
+        mandatoryString("key", key);
+        mandatory("value", value);
+
+        try
+        {
+            jsonObject.put(key, value);
+        }
+        catch (JSONException error)
+        {
+            throw new WebScriptException(Status.STATUS_BAD_REQUEST, "Could not put the key '" + key + "' with the value '" + value + "' to the json object.");
+        }
+    }
+
+    /**
+     * Gets the value of an element from a json array at the given index
+     *
+     * @param jsonArray The json array
+     * @param index The index
+     * @return The value of the element
+     */
+    public static Object getJSONArrayValue(JSONArray jsonArray, int index)
+    {
+        mandatory("jsonArray", jsonArray);
+
+        Object value;
+
+        try
+        {
+            value = jsonArray.get(index);
+        }
+        catch (JSONException error)
+        {
+            throw new WebScriptException(Status.STATUS_BAD_REQUEST, "Could not get value for the index '" + index + "' from the JSON Array.", error);
+        }
+
+        return value;
+    }
+}