Form.java
/**
*
* Copyright 2003-2007 Jive Software.
*
* 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.jivesoftware.smackx.xdata;
import java.util.ArrayList;
import java.util.Iterator;
import java.util.List;
import java.util.StringTokenizer;
import org.jivesoftware.smack.packet.Stanza;
import org.jivesoftware.smackx.xdata.packet.DataForm;
/**
* Represents a Form for gathering data. The form could be of the following types:
* <ul>
* <li>form -> Indicates a form to fill out.</li>
* <li>submit -> The form is filled out, and this is the data that is being returned from
* the form.</li>
* <li>cancel -> The form was cancelled. Tell the asker that piece of information.</li>
* <li>result -> Data results being returned from a search, or some other query.</li>
* </ul>
*
* Depending of the form's type different operations are available. For example, it's only possible
* to set answers if the form is of type "submit".
*
* @see <a href="http://xmpp.org/extensions/xep-0004.html">XEP-0004 Data Forms</a>
*
* @author Gaston Dombiak
*/
public class Form {
private DataForm dataForm;
/**
* Returns a new ReportedData if the packet is used for gathering data and includes an
* extension that matches the elementName and namespace "x","jabber:x:data".
*
* @param packet the packet used for gathering data.
* @return the data form parsed from the packet or <tt>null</tt> if there was not
* a form in the packet.
*/
public static Form getFormFrom(Stanza packet) {
// Check if the packet includes the DataForm extension
DataForm dataForm = DataForm.from(packet);
if (dataForm != null) {
if (dataForm.getReportedData() == null)
return new Form(dataForm);
}
// Otherwise return null
return null;
}
/**
* Creates a new Form that will wrap an existing DataForm. The wrapped DataForm must be
* used for gathering data.
*
* @param dataForm the data form used for gathering data.
*/
public Form(DataForm dataForm) {
this.dataForm = dataForm;
}
/**
* Creates a new Form of a given type from scratch.
*
* @param type the form's type (e.g. form, submit,cancel,result).
*/
public Form(DataForm.Type type) {
this.dataForm = new DataForm(type);
}
/**
* Adds a new field to complete as part of the form.
*
* @param field the field to complete.
*/
public void addField(FormField field) {
dataForm.addField(field);
}
/**
* Sets a new String value to a given form's field. The field whose variable matches the
* requested variable will be completed with the specified value. If no field could be found
* for the specified variable then an exception will be raised.<p>
*
* If the value to set to the field is not a basic type (e.g. String, boolean, int, etc.) you
* can use this message where the String value is the String representation of the object.
*
* @param variable the variable name that was completed.
* @param value the String value that was answered.
* @throws IllegalStateException if the form is not of type "submit".
* @throws IllegalArgumentException if the form does not include the specified variable or
* if the answer type does not correspond with the field type..
*/
public void setAnswer(String variable, String value) {
FormField field = getField(variable);
if (field == null) {
throw new IllegalArgumentException("Field not found for the specified variable name.");
}
switch (field.getType()) {
case text_multi:
case text_private:
case text_single:
case jid_single:
case hidden:
break;
default:
throw new IllegalArgumentException("This field is not of type String.");
}
setAnswer(field, value);
}
/**
* Sets a new int value to a given form's field. The field whose variable matches the
* requested variable will be completed with the specified value. If no field could be found
* for the specified variable then an exception will be raised.
*
* @param variable the variable name that was completed.
* @param value the int value that was answered.
* @throws IllegalStateException if the form is not of type "submit".
* @throws IllegalArgumentException if the form does not include the specified variable or
* if the answer type does not correspond with the field type.
*/
public void setAnswer(String variable, int value) {
FormField field = getField(variable);
if (field == null) {
throw new IllegalArgumentException("Field not found for the specified variable name.");
}
validateThatFieldIsText(field);
setAnswer(field, value);
}
/**
* Sets a new long value to a given form's field. The field whose variable matches the
* requested variable will be completed with the specified value. If no field could be found
* for the specified variable then an exception will be raised.
*
* @param variable the variable name that was completed.
* @param value the long value that was answered.
* @throws IllegalStateException if the form is not of type "submit".
* @throws IllegalArgumentException if the form does not include the specified variable or
* if the answer type does not correspond with the field type.
*/
public void setAnswer(String variable, long value) {
FormField field = getField(variable);
if (field == null) {
throw new IllegalArgumentException("Field not found for the specified variable name.");
}
validateThatFieldIsText(field);
setAnswer(field, value);
}
/**
* Sets a new float value to a given form's field. The field whose variable matches the
* requested variable will be completed with the specified value. If no field could be found
* for the specified variable then an exception will be raised.
*
* @param variable the variable name that was completed.
* @param value the float value that was answered.
* @throws IllegalStateException if the form is not of type "submit".
* @throws IllegalArgumentException if the form does not include the specified variable or
* if the answer type does not correspond with the field type.
*/
public void setAnswer(String variable, float value) {
FormField field = getField(variable);
if (field == null) {
throw new IllegalArgumentException("Field not found for the specified variable name.");
}
validateThatFieldIsText(field);
setAnswer(field, value);
}
/**
* Sets a new double value to a given form's field. The field whose variable matches the
* requested variable will be completed with the specified value. If no field could be found
* for the specified variable then an exception will be raised.
*
* @param variable the variable name that was completed.
* @param value the double value that was answered.
* @throws IllegalStateException if the form is not of type "submit".
* @throws IllegalArgumentException if the form does not include the specified variable or
* if the answer type does not correspond with the field type.
*/
public void setAnswer(String variable, double value) {
FormField field = getField(variable);
if (field == null) {
throw new IllegalArgumentException("Field not found for the specified variable name.");
}
validateThatFieldIsText(field);
setAnswer(field, value);
}
private static void validateThatFieldIsText(FormField field) {
switch(field.getType()) {
case text_multi:
case text_private:
case text_single:
break;
default:
throw new IllegalArgumentException("This field is not of type text (multi, private or single).");
}
}
/**
* Sets a new boolean value to a given form's field. The field whose variable matches the
* requested variable will be completed with the specified value. If no field could be found
* for the specified variable then an exception will be raised.
*
* @param variable the variable name that was completed.
* @param value the boolean value that was answered.
* @throws IllegalStateException if the form is not of type "submit".
* @throws IllegalArgumentException if the form does not include the specified variable or
* if the answer type does not correspond with the field type.
*/
public void setAnswer(String variable, boolean value) {
FormField field = getField(variable);
if (field == null) {
throw new IllegalArgumentException("Field not found for the specified variable name.");
}
if (field.getType() != FormField.Type.bool) {
throw new IllegalArgumentException("This field is not of type boolean.");
}
setAnswer(field, (value ? "1" : "0"));
}
/**
* Sets a new Object value to a given form's field. In fact, the object representation
* (i.e. #toString) will be the actual value of the field.<p>
*
* If the value to set to the field is not a basic type (e.g. String, boolean, int, etc.) you
* will need to use {@link #setAnswer(String, String)} where the String value is the
* String representation of the object.<p>
*
* Before setting the new value to the field we will check if the form is of type submit. If
* the form isn't of type submit means that it's not possible to complete the form and an
* exception will be thrown.
*
* @param field the form field that was completed.
* @param value the Object value that was answered. The object representation will be the
* actual value.
* @throws IllegalStateException if the form is not of type "submit".
*/
private void setAnswer(FormField field, Object value) {
if (!isSubmitType()) {
throw new IllegalStateException("Cannot set an answer if the form is not of type " +
"\"submit\"");
}
field.resetValues();
field.addValue(value.toString());
}
/**
* Sets a new values to a given form's field. The field whose variable matches the requested
* variable will be completed with the specified values. If no field could be found for
* the specified variable then an exception will be raised.<p>
*
* The Objects contained in the List could be of any type. The String representation of them
* (i.e. #toString) will be actually used when sending the answer to the server.
*
* @param variable the variable that was completed.
* @param values the values that were answered.
* @throws IllegalStateException if the form is not of type "submit".
* @throws IllegalArgumentException if the form does not include the specified variable.
*/
public void setAnswer(String variable, List<String> values) {
if (!isSubmitType()) {
throw new IllegalStateException("Cannot set an answer if the form is not of type " +
"\"submit\"");
}
FormField field = getField(variable);
if (field != null) {
// Check that the field can accept a collection of values
switch (field.getType()) {
case jid_multi:
case list_multi:
case list_single:
case text_multi:
case hidden:
break;
default:
throw new IllegalArgumentException("This field only accept list of values.");
}
// Clear the old values
field.resetValues();
// Set the new values. The string representation of each value will be actually used.
field.addValues(values);
}
else {
throw new IllegalArgumentException("Couldn't find a field for the specified variable.");
}
}
/**
* Sets the default value as the value of a given form's field. The field whose variable matches
* the requested variable will be completed with its default value. If no field could be found
* for the specified variable then an exception will be raised.
*
* @param variable the variable to complete with its default value.
* @throws IllegalStateException if the form is not of type "submit".
* @throws IllegalArgumentException if the form does not include the specified variable.
*/
public void setDefaultAnswer(String variable) {
if (!isSubmitType()) {
throw new IllegalStateException("Cannot set an answer if the form is not of type " +
"\"submit\"");
}
FormField field = getField(variable);
if (field != null) {
// Clear the old values
field.resetValues();
// Set the default value
for (String value : field.getValues()) {
field.addValue(value);
}
}
else {
throw new IllegalArgumentException("Couldn't find a field for the specified variable.");
}
}
/**
* Returns a List of the fields that are part of the form.
*
* @return a List of the fields that are part of the form.
*/
public List<FormField> getFields() {
return dataForm.getFields();
}
/**
* Returns the field of the form whose variable matches the specified variable.
* The fields of type FIXED will never be returned since they do not specify a
* variable.
*
* @param variable the variable to look for in the form fields.
* @return the field of the form whose variable matches the specified variable.
*/
public FormField getField(String variable) {
if (variable == null || variable.equals("")) {
throw new IllegalArgumentException("Variable must not be null or blank.");
}
// Look for the field whose variable matches the requested variable
for (FormField field : getFields()) {
if (variable.equals(field.getVariable())) {
return field;
}
}
return null;
}
/**
* Returns the instructions that explain how to fill out the form and what the form is about.
*
* @return instructions that explain how to fill out the form.
*/
public String getInstructions() {
StringBuilder sb = new StringBuilder();
// Join the list of instructions together separated by newlines
for (Iterator<String> it = dataForm.getInstructions().iterator(); it.hasNext();) {
sb.append(it.next());
// If this is not the last instruction then append a newline
if (it.hasNext()) {
sb.append("\n");
}
}
return sb.toString();
}
/**
* Returns the description of the data. It is similar to the title on a web page or an X
* window. You can put a <title/> on either a form to fill out, or a set of data results.
*
* @return description of the data.
*/
public String getTitle() {
return dataForm.getTitle();
}
/**
* Returns the meaning of the data within the context. The data could be part of a form
* to fill out, a form submission or data results.
*
* @return the form's type.
*/
public DataForm.Type getType() {
return dataForm.getType();
}
/**
* Sets instructions that explain how to fill out the form and what the form is about.
*
* @param instructions instructions that explain how to fill out the form.
*/
public void setInstructions(String instructions) {
// Split the instructions into multiple instructions for each existent newline
ArrayList<String> instructionsList = new ArrayList<String>();
StringTokenizer st = new StringTokenizer(instructions, "\n");
while (st.hasMoreTokens()) {
instructionsList.add(st.nextToken());
}
// Set the new list of instructions
dataForm.setInstructions(instructionsList);
}
/**
* Sets the description of the data. It is similar to the title on a web page or an X window.
* You can put a <title/> on either a form to fill out, or a set of data results.
*
* @param title description of the data.
*/
public void setTitle(String title) {
dataForm.setTitle(title);
}
/**
* Returns a DataForm that serves to send this Form to the server. If the form is of type
* submit, it may contain fields with no value. These fields will be removed since they only
* exist to assist the user while editing/completing the form in a UI.
*
* @return the wrapped DataForm.
*/
public DataForm getDataFormToSend() {
if (isSubmitType()) {
// Create a new DataForm that contains only the answered fields
DataForm dataFormToSend = new DataForm(getType());
for(FormField field : getFields()) {
if (!field.getValues().isEmpty()) {
dataFormToSend.addField(field);
}
}
return dataFormToSend;
}
return dataForm;
}
/**
* Returns true if the form is a form to fill out.
*
* @return if the form is a form to fill out.
*/
private boolean isFormType() {
return DataForm.Type.form == dataForm.getType();
}
/**
* Returns true if the form is a form to submit.
*
* @return if the form is a form to submit.
*/
private boolean isSubmitType() {
return DataForm.Type.submit == dataForm.getType();
}
/**
* Returns a new Form to submit the completed values. The new Form will include all the fields
* of the original form except for the fields of type FIXED. Only the HIDDEN fields will
* include the same value of the original form. The other fields of the new form MUST be
* completed. If a field remains with no answer when sending the completed form, then it won't
* be included as part of the completed form.<p>
*
* The reason why the fields with variables are included in the new form is to provide a model
* for binding with any UI. This means that the UIs will use the original form (of type
* "form") to learn how to render the form, but the UIs will bind the fields to the form of
* type submit.
*
* @return a Form to submit the completed values.
*/
public Form createAnswerForm() {
if (!isFormType()) {
throw new IllegalStateException("Only forms of type \"form\" could be answered");
}
// Create a new Form
Form form = new Form(DataForm.Type.submit);
for (FormField field : getFields()) {
// Add to the new form any type of field that includes a variable.
// Note: The fields of type FIXED are the only ones that don't specify a variable
if (field.getVariable() != null) {
FormField newField = new FormField(field.getVariable());
newField.setType(field.getType());
form.addField(newField);
// Set the answer ONLY to the hidden fields
if (field.getType() == FormField.Type.hidden) {
// Since a hidden field could have many values we need to collect them
// in a list
List<String> values = new ArrayList<String>();
for (String value : field.getValues()) {
values.add(value);
}
form.setAnswer(field.getVariable(), values);
}
}
}
return form;
}
}