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Improve Performance with Multiple Row Inserts and Fetches with Oracle SQL Stored Procedures and Java Spring

I currently have stored procedures for Oracle SQL, version 18c, for both inserting and fetching multiple rows of data from one parent table and one child table, being called from my Java Spring Boot application. Everything works fine, but it is extremely slow, for only a few rows of data.
When only inserting 70 records between the two, it takes up to 267 seconds into empty tables. Fetching that same data back out takes about 40 seconds.
Any help would be greatly appreciated or if there is any additional information needed from me.
Below is a cut down and renamed version of my stored procedures for my parent and child tables, actual parent table has 32 columns and child has 11.
PROCEDURE processParentData(
i_field_one varchar2,
v_parent_id OUT number) is
v_new PARENT%ROWTYPE;
BEGIN
v_new.id := ROW_SEQUENCE.nextval;
v_new.insert_time := systimestamp;
v_new.field_one := i_field_one;
insert into PARENT values v_new;
v_parent_id := v_new.id;
END;
PROCEDURE readParentData(
i_field_one IN varchar2,
v_parent OUT SYS_REFCURSOR) AS
BEGIN
OPEN v_parent FOR select h.* from PARENT h
where h.field_one = i_field_one;
END;
PROCEDURE processChild(
i_field_one varchar2,
i_parent_id number) is
v_new CHILD%ROWTYPE;
BEGIN
v_new.id := ROW_SEQUENCE.nextval;
v_new.insert_time := systimestamp;
v_new.field_one := i_field_one;
v_new.parent_id := i_parent_id;
insert into CHILD values v_new;
END;
PROCEDURE readChild(
i_parent_id IN number,
v_child OUT SYS_REFCURSOR) AS
BEGIN
OPEN v_child FOR select h.* from CHILD h
where h.parent_id = i_parent_id;
END;
For my Java code I am using Spring JDBC. After I get the parent data, I then fetch each child data by looping through the parent data and calling readChild with the parent ID for each.
var simpleJdbcCall = new SimpleJdbcCall(jdbcTemplate)
.withCatalogName("PARENT_PACKAGE")
.withProcedureName("processParentData");
SqlParameterSource sqlParameterSource = new MapSqlParameterSource()
.addValue("i_field_one", locationId)
.addValue("v_parent_id", null);
Map<String, Object> out = simpleJdbcCall.execute(sqlParameterSource);
var stopId = (BigDecimal) out.get("v_parent_id");
return stopId.longValue();
var simpleJdbcCall = new SimpleJdbcCall(jdbcTemplate)
.withCatalogName("PARENT_PACKAGE")
.withProcedureName("readParentData")
.returningResultSet("v_parent", BeanPropertyRowMapper.newInstance(Parent.class));
SqlParameterSource sqlParameterSource = new MapSqlParameterSource()
.addValue("i_field_one", location.getId());
Map<String, Object> out = simpleJdbcCall.execute(sqlParameterSource);
return (List<Parent>) out.get("v_parent");
UPDATE 1: As I know and have tested, using the same data and tables, if I use pure JDBC or JPA/Hibernate for inserting and fetching to the tables directly and avoid using stored procedures, then the whole process of inserting and fetching only takes a few seconds.
The issue is, at the company I work at, they have set a policy that all applications going forward are not allowed to have direct read/write access to the database and everything must be done through stored procedures, they say for security reasons. Meaning I need to workout how to do the same thing we have been doing for years with direct read/write access, now with only using Oracle stored procedures.
UPDATE 2: Adding my current Java code for fetching the child data.
for (Parent parent : parents) {
parent.setChilds(childRepository.readChildByParentId(parent.getId()));
}
public List<Child> readChildByParentId(long parentId) {
var simpleJdbcCall = new SimpleJdbcCall(jdbcTemplate)
.withCatalogName("CHILD_PACKAGE")
.withProcedureName("readChild")
.returningResultSet("v_child", BeanPropertyRowMapper.newInstance(Child.class));
SqlParameterSource sqlParameterSource = new MapSqlParameterSource()
.addValue("i_parent_id ", parentId);
Map<String, Object> out = simpleJdbcCall.execute(sqlParameterSource);
return (List<Child>) out.get("v_child");
}

The problem is that the insert you are trying to perform using the stored procedure is not optimized, because you are calling the database every time you try to insert a row.
I strongly recommend you to transform the data to XML (for example, you can also use CSV) and pass it to the procedure, then loop over it and perform the inserts that you need.
Here is an example made using Oracle:
CREATE OR REPLACE PROCEDURE MY_SCHEMA.my_procedure(xmlData clob) IS
begin
FOR CONTACT IN (SELECT *
FROM XMLTABLE(
'/CONTACTS/CONTACT' PASSING
XMLTYPE(contactes)
COLUMNS param_id FOR ORDINALITY
,id NUMBER PATH 'ID'
,name VARCHAR2(100) PATH 'NAME'
,surname VARCHAR2(100) PATH 'SURNAME'
))
LOOP
INSERT INTO PARENT_TABLE VALUES CONTACT.id, CONTACT.name, CONTACT.surname;
end loop;
end;
The XML, you can use a String to pass the data to the procedure:
<CONTACTS>
<CONTACT>
<ID>1</ID>
<NAME>Jonh</NAME>
<SURNAME>Smith</SURNAME>
</CONTACT>
<CONTACTS>

For my Java code I am using Spring JDBC. After I get the parent data, I then fetch each child data by looping through the parent data and calling readChild with the parent ID for each.
Instead of fetching child data in loop, you can modify your procedure to accept list of parent id and return all the data in one call.
It will be helpful if you share spring boot for loop code as well.
Update
Instead of fetching single parent details, you should have update your code like this. Also you have to update your procedure as well.
List<Long> parents = new ArrayList<>();
for (Parent parent : parents) {
parents.add(parent.getId());
}
You can use java streams but that is secondary things.
Now you have to modify your procedure and method to accept multiple parent ids.
List<Child> children = childRepository.readreadChildByParentId(parents);
public List<Child> readChildByParentId(long parentId) {
var simpleJdbcCall = new SimpleJdbcCall(jdbcTemplate)
.withCatalogName("CHILD_PACKAGE")
.withProcedureName("readChild")
.returningResultSet("v_child", BeanPropertyRowMapper.newInstance(Child.class));
SqlParameterSource sqlParameterSource = new MapSqlParameterSource()
.addValue("i_parent_id ", parentId);
Map<String, Object> out = simpleJdbcCall.execute(sqlParameterSource);
return (List<Child>) out.get("v_child");
}
After having all the children you can set parent children via java code.
P.S.
Could you please check if you fetch parents with children if parent is coming from the database?

Your performance problems are probably related with the number of operations performed against the database: you are iterating in Java your collections, and interacting with the database in every iteration. You need to minimize the number of operations performed.
One possible solution can be the use of the standard STRUCT and ARRAY Oracle types. Please, consider for instance the following example:
public static void insertData() throws SQLException {
DriverManagerDataSource dataSource = ...
JdbcTemplate jdbcTemplate = new JdbcTemplate(dataSource);
jdbcTemplate.setResultsMapCaseInsensitive(true);
SimpleJdbcCall insertDataCall = new SimpleJdbcCall(jdbcTemplate)
.withCatalogName("parent_child_pkg")
.withProcedureName("insert_data")
.withoutProcedureColumnMetaDataAccess()
.useInParameterNames("p_parents")
.declareParameters(
new SqlParameter("p_parents", OracleTypes.ARRAY, "PARENT_ARRAY")
);
OracleConnection connection = null;
try {
connection = insertDataCall
.getJdbcTemplate()
.getDataSource()
.getConnection()
.unwrap(OracleConnection.class)
;
List<Parent> parents = new ArrayList<>(100);
Parent parent = null;
List<Child> chilren = null;
Child child = null;
for (int i = 0; i < 100; i++) {
parent = new Parent();
parents.add(parent);
parent.setId((long) i);
parent.setName("parent-" + i);
chilren = new ArrayList<>(1000);
parent.setChildren(chilren);
for (int j = 0; j < 1000; j++) {
child = new Child();
chilren.add(child);
child.setId((long) j);
child.setName("parent-" + j);
}
}
System.out.println("Inserting data...");
StopWatch stopWatch = new StopWatch();
stopWatch.start("insert-data");
StructDescriptor parentTypeStructDescriptor = StructDescriptor.createDescriptor("PARENT_TYPE", connection);
ArrayDescriptor parentArrayDescriptor = ArrayDescriptor.createDescriptor("PARENT_ARRAY", connection);
StructDescriptor childTypeStructDescriptor = StructDescriptor.createDescriptor("CHILD_TYPE", connection);
ArrayDescriptor childArrayDescriptor = ArrayDescriptor.createDescriptor("CHILD_ARRAY", connection);
Object[] parentArray = new Object[parents.size()];
int pi = 0;
for (Parent p : parents) {
List<Child> children = p.getChildren();
Object[] childArray = new Object[children.size()];
int ci = 0;
for (Child c : children) {
Object[] childrenObj = new Object[2];
childrenObj[0] = c.getId();
childrenObj[1] = c.getName();
STRUCT childStruct = new STRUCT(childTypeStructDescriptor, connection, childrenObj);
childArray[ci++] = childStruct;
}
ARRAY childrenARRAY = new ARRAY(childArrayDescriptor, connection, childArray);
Object[] parentObj = new Object[3];
parentObj[0] = p.getId();
parentObj[1] = p.getName();
parentObj[2] = childrenARRAY;
STRUCT parentStruct = new STRUCT(parentTypeStructDescriptor, connection, parentObj);
parentArray[pi++] = parentStruct;
}
ARRAY parentARRAY = new ARRAY(parentArrayDescriptor, connection, parentArray);
Map in = Collections.singletonMap("p_parents", parentARRAY);
insertDataCall.execute(in);
connection.commit();
stopWatch.stop();
System.out.println(stopWatch.prettyPrint());
} catch (Throwable t) {
t.printStackTrace();
connection.rollback();
} finally {
if (connection != null) {
try {
connection.close();
} catch (Throwable nested) {
nested.printStackTrace();
}
}
}
}
Where:
CREATE OR REPLACE TYPE child_type AS OBJECT (
id NUMBER,
name VARCHAR2(512)
);
CREATE OR REPLACE TYPE child_array
AS TABLE OF child_type;
CREATE OR REPLACE TYPE parent_type AS OBJECT (
id NUMBER,
name VARCHAR2(512),
children child_array
);
CREATE OR REPLACE TYPE parent_array
AS TABLE OF parent_type;
CREATE SEQUENCE PARENT_SEQ INCREMENT BY 1 MINVALUE 1;
CREATE SEQUENCE CHILD_SEQ INCREMENT BY 1 MINVALUE 1;
CREATE TABLE parent_table (
id NUMBER,
name VARCHAR2(512)
);
CREATE TABLE child_table (
id NUMBER,
name VARCHAR2(512),
parent_id NUMBER
);
CREATE OR REPLACE PACKAGE parent_child_pkg AS
PROCEDURE insert_data(p_parents PARENT_ARRAY);
END;
CREATE OR REPLACE PACKAGE BODY parent_child_pkg AS
PROCEDURE insert_data(p_parents PARENT_ARRAY) IS
l_parent_id NUMBER;
l_child_id NUMBER;
BEGIN
FOR i IN 1..p_parents.COUNT LOOP
SELECT parent_seq.nextval INTO l_parent_id FROM dual;
INSERT INTO parent_table(id, name)
VALUES(l_parent_id, p_parents(i).name);
FOR j IN 1..p_parents(i).children.COUNT LOOP
SELECT child_seq.nextval INTO l_child_id FROM dual;
INSERT INTO child_table(id, name, parent_id)
VALUES(l_child_id, p_parents(i).name, l_parent_id);
END LOOP;
END LOOP;
END;
END;
And Parent and Child are simple POJOs:
import java.util.ArrayList;
import java.util.List;
public class Parent {
private Long id;
private String name;
private List<Child> children = new ArrayList<>();
public Long getId() {
return id;
}
public void setId(Long id) {
this.id = id;
}
public String getName() {
return name;
}
public void setName(String name) {
this.name = name;
}
public List<Child> getChildren() {
return children;
}
public void setChildren(List<Child> children) {
this.children = children;
}
}
public class Child {
private Long id;
private String name;
public Long getId() {
return id;
}
public void setId(Long id) {
this.id = id;
}
public String getName() {
return name;
}
public void setName(String name) {
this.name = name;
}
}
Please, forgive for the code legibility and incorrect error handling, I will improve the answer later including some information about obtaining the data as well.

The times you mention are horrible indeed. A big boost forward in performance will be to work set based. This means reducing the row by row database calls.
Row by row is synonymous for slow, especially when network round trips are involved.
One call to get the parent.
One call to get the set of children and process them. The jdbc fetch size is a nice tunable here. Give it a chance to work for you.

You do not need to use DYNAMIC SQL OPEN v_parent FOR and also it is not clear how the view v_parent is defined.
Try to check exec plan of this query:
FOR select h.* from PARENT h where h.field_one = ?;
Usually returning recordset via SYS_REFCURSOR increases performance when you return more (let's say) than 10K records.

The SimpleJdbcCall object can be reused in your scenario as only the parameters changes. The SimpleJdbcCall object compiles the jdbc statement on the first invocation. It does some meta-data fetching and it interacts with the Database for that. So, having separate objects would mean fetching same metadata that many times which is not needed.
So, I suggest to initialise all the 4 SimpleJdbcCall objects in the very beginning and then work with them.
var insertParentJdbcCall = new SimpleJdbcCall(jdbcTemplate)
.withCatalogName("PARENT_PACKAGE")
.withProcedureName("processParentData");
var readParentJdbcCall = new SimpleJdbcCall(jdbcTemplate)
.withCatalogName("PARENT_PACKAGE")
.withProcedureName("readParentData")
.returningResultSet("v_parent", BeanPropertyRowMapper.newInstance(Parent.class));
var insertChildJdbcCall = new SimpleJdbcCall(jdbcTemplate)
.withCatalogName("CHILD_PACKAGE")
.withProcedureName("processChildData");
var readChildJdbcCall = new SimpleJdbcCall(jdbcTemplate)
.withCatalogName("CHILD_PACKAGE")
.withProcedureName("readChild")
.returningResultSet("v_child", BeanPropertyRowMapper.newInstance(Child.class));

Why isn't my List<Object> displaying on my webpage?

I'm trying to display the contents of a List<> of objects that are linked to the currently logged in user on a jsp page. The object is successfully created and stored in the database with a user_id of the user who created it, and with a simple system.out.print debugger I can see its added to the List.
But when I try to display this on the NewFile.jsp webpage its as if the the List is empty. There is no error, instead the page is just blank as if there is no List to iterate through.
Skill method in UserController
#RequestMapping(value = "/skill", method = RequestMethod.POST)
public String skill(#ModelAttribute("skillForm") Skill skillForm, BindingResult bindingResult, Model model, Principal principal) {
skillValidator.validate(skillForm, bindingResult);
if (bindingResult.hasErrors()) {
return "skill";
}
// Adds skill object to database and adding it to Users skill list
String name = principal.getName();
skillService.save(skillForm, name);
User currentUser = userService.findByUsername(principal.getName());
currentUser.addSkill(skillForm);
// Debug here shows that the list contains correct data and the list size
System.out.println(skillForm.getSkillName());
System.out.println(skillForm.getCategory());
System.out.println(currentUser.getSkills().size());
// Attempting to pass the list to NewFile.jsp to be displayed
List<Skill> savedSkills = currentUser.getSkills();
for(int i = 0; i < savedSkills.size(); i++) {
model.addAttribute("skills", savedSkills);
/*model.addAttribute("currentUser", currentUser);*/
}
return "NewFile";
}
NewFile.jsp
<table>
<c:forEach var="o" items="${savedSkills}" >
<tr>
<td>Skill Name:<c:out value = "${o.skillName}"/></td>
<td>Category:<c:out value = "${o.category}"/> </td>
</tr>
</c:forEach>
</table>

There are some mistakes. First you don't need a loop.
List<Skill> savedSkills = currentUser.getSkills();
model.addAttribute("skills", savedSkills);
Second, your EL has the wrong argument name, just like the others had stated.
<c:forEach var="o" items="${skills}" >

You need to specify what skill to be added , you are adding the List as an attribute but you need to the object that's inside it
for(int i = 0; i < savedSkills.size(); i++) {
model.addAttribute("skills", savedSkills[i]);
/*model.addAttribute("currentUser", currentUser);*/
}

Try by adding the code model.addAttribute("savedSkills", savedSkills); before the return statement. You haven't add the model attribute named with "savedSkills".

Populating Thymeleaf rows, with one of column referenced to another table(Database).Need another column of referenced Table to display

I am beginner with springboot. I came across a situation.Ok, let me give table structure before I explain.
Expenses
expensesId, categories,
Categories
categoryId, categoryname
Expenses table is referring to category table with categoryId.
I am able to populate datatable with expensesList that was sent from a controller to view successfully. But my problem is I get columnid in populated but I wish to populate that column with categoryname instead. I thought for possible solutions for some time and I come up with stupid Idea using If the condition in thymeleaf of mapping categoryId with categoryName but I don't wish to go for that part as I can have more categories growing in future and code is difficult to maintain.
I could really use some help on this.
Link to git project
expensespage link
expenses controller link
Please do provide links if a solution is already available which I missed during my google search on this issue.
Apologies for bad english for Title part as I cannot squeeze question further.

I just added category object containing Id and name to every expenses object in
Expenses Object List and passed to controller. Now I can directly use CategoryName in View with Thymeleaf as follows
<td th:text="${expense.categories.categoryname}"></td>>
What I changed in controller.
Before
#RequestMapping(value = "/expenses")
public String toExpensesPage(Model model) {
Authentication authentication = SecurityContextHolder.getContext().getAuthentication();
User user = monitorService.getUserByUserName(authentication.getName()).get(0);
List<Categories> categoriesList = monitorService.getAllCategories();
model.addAttribute("expenses",new Expenses());
if(categoriesList != null) {
model.addAttribute("categories",categoriesList);
}
List<Expenses> expensesList = monitorService.getAllExpensesActive(user.getUserid());
model.addAttribute("expensesList",expensesList);
return "common/expensespage";
}
To.
#RequestMapping(value = "/expenses")
public String toExpensesPage(Model model) {
Map<Integer,String> categoryMap = new HashMap<Integer, String>();
Authentication authentication = SecurityContextHolder.getContext().getAuthentication();
User user = monitorService.getUserByUserName(authentication.getName()).get(0);
/* getting Category List This contains both categoryId and categoryname */
List<Categories> categoriesList = monitorService.getAllCategories();
/* Using hashmap to map id to name so we dont need to iterate categoryList or call to database with category Id..*/
for(int i = 0; i < categoriesList.size();i++){
categoryMap.put(categoriesList.get(i).getCategoryid(),
categoriesList.get(i).getCategoryname());
}
model.addAttribute("expenses",new Expenses());
if(categoriesList != null) {
model.addAttribute("categories",categoriesList);
}
List<Expenses> expensesList = monitorService.getAllExpensesActive(user.getUserid());
/*Assigning category object to expenses object*/
for(int i = 0; i < expensesList.size();i++){
Categories categories = new Categories();
categories.setCategoryid(expensesList.get(i).getCategories().getCategoryid());
categories.setCategoryname(categoryMap.get(expensesList.get(i).getCategories().getCategoryid()));
expensesList.get(i).setCategories(categories);
}
model.addAttribute("expensesList",expensesList);
return "common/expensespage";
}
Added Comment's inside code on how I did. Hope someone find it helpful.

Group values from a parameter list in a loop according to the prefix of the parameter

I am fetching a param list from my jsp which I need to identify according to the prefix so that I can set the values in my entity class.
The parameter names looks like the below:
List<String> reqParamNames = Arrays.asList("1_component_role", "2_component_role", "3_component_role",
"4_component_role", "1_survey_wt", "2_survey_wt", "3_survey_wt", "4_survey_wt", "1dynaGroup1", "1component_role1", "1wt1", "2dynaGroup1", "2component_role1", "2wt1", "3dynaGroup1",
"3component_role1", "3wt1", "4dynaGroup1", "4component_role1", "4wt1");
Now, from the above list, I need to get the param according to the prefix, i.e.1,2,3,4 etc. Once grouped correctly, I would need to set it to my Entity class so that I can save the parameters in my table using Hibernate.
I am unable to set the values for the dynamic table.
#RequestMapping(value = { "dynamicSettings/persist" }, method = RequestMethod.POST)
public String saveComponents(HttpServletRequest request, HttpServletResponse response,
Model model) {
LOG.debug("Entering persist area :: ");
Locale locale = LocaleUtil.getLocale();
// ToDo: validation for form
//For dynamic tables
List<String> reqParamNames = (List<String>) Collections.list((Enumeration<String>)request.getParameterNames());
for(int i =0; i < reqParamNames.size(); i++){
System.out.println("Param names are {} ::"+ reqParamNames.get(i));
String paramName = reqParamNames.get(i);
Matcher m = Pattern.compile("[^0-9]*([0-9]+).*").matcher(paramName);
if (m.matches()) {
System.out.println("Number ::" +m.group(1)); // Need to comment/remove this post development
}
System.out.println("ParamNumber ::" +""+m.group(1));
String attributeValue = request.getParameter(paramName);
System.out.println("Param Name ::"+paramName+"::: Attribute value ::"+attributeValue);
DynamicComponentSettings dynamicSettings = new DynamicComponentSettings();
if( i == paramNumber){
String group_type = request.getParameter("groupType"+i);
String component_role = request.getParameter("component_role"+i);
String survey_weight = request.getParameter("wt"+i);
System.out.println("Group Type ::"+group_type+ "::Component Role::" +component_role+ "::Survey Weight::"+survey_weight);
if(!StringUtils.isEmpty(group_type) && StringUtils.isEmpty(component_role)&&!StringUtils.isEmpty(survey_weight)){
Double survey_wt = Double.parseDouble(survey_weight);
dynamicSettings.setSurvey_wt(survey_wt);
dynamicSettings.setGroup_type(group_type);
dynamicSettings.setComponent_role(component_role);
}
}
dynamicComponentService.saveDynamicComponents(dynamicSettings);
}
**//For concrete table**
List<DynamicComponentSettings> resultList = dynamicComponentService.loadAllDynamicComponents();
for(DynamicComponentSettings component : resultList)
{
String _survey_wt = request.getParameter(component.getPk1().toString() + "survey_wt");
String _groupRoleType = request.getParameter(component.getPk1().toString() + "group_type");
String _componentRole = request.getParameter(component.getPk1().toString() + "component_role");
if(!StringUtils.isEmpty(_survey_wt) && StringUtils.isEmpty(_groupRoleType)&&!StringUtils.isEmpty(_componentRole)){
Double survey_wt = Double.parseDouble(_survey_wt);
component.setSurvey_wt(survey_wt);
component.setGroup_type(_groupRoleType);
component.setComponent_role(_componentRole);
}
dynamicComponentService.saveDynamicComponents(component);
}
return "redirect:" + "some url";
}
The concrete table works correctly, i.e. saving values correctly.
Entity class
<package declaration>
<imports>
#Entity
#Table(name = "dynamic_components")
public class DynamicComponentSettings {
/** The pk1. */
#Id
#SequenceGenerator(name = "dynamic_components_seq", sequenceName = "dynamic_components_seq", allocationSize = 1)
#GeneratedValue(strategy = GenerationType.AUTO, generator = "dynamic_components_seq")
private Long pk1;
private String group_type;
private String component_role;
private Double survey_wt;
<getters and setters>
}
Please provide your inputs and provide guidance as how to save the dynamic table values.

I managed to figure out the problems and fix it. There are multiple problems in that code sample. For eg. the loops are incorrect, the approach to match with the main loop was horribly wrong.
I had to get the prefix and suffix for each item, loop correctly[i.e. first get the suffix and prefix of the table and then based on suffix match, iterate through the prefix like rows] and put each dynamic table data with suffix being the key and prefix+data+suffix being the values into a Map containing linked lists. After that, I had to loop again through the Map containing the lists to set the values to my entity class correctly.
Please pardon me for not posting the code again as the method is quite long and may not be of much help. In any case, if someone does want to see how this was solved, please let me know.
Thanks for your time.

Play Framework 2.0 form helper: from checkbox to List<String>

I have a model that contains a String and a list:
public String title;
public List<String> topics;
In index.scala.html I use a form to add new items:
#form(routes.Application.newPaper()) {
#inputText(paperForm("title"))
<input type="submit" value="Create">
}
with a simple String, this works nicely. But I would like to show checkboxes
#for(t <- topics) {
<input type='checkbox' name='topic' value=#t>#t <br>
}
and subsequently add all checked 'topics' to the List<String> topics; of my new item. How can I process the checkboxes within #form{ ... }?

I am using Play!Framework 2.1.0, below is the solution :
1. In the scala template, you must give all checkbox name like this:
#form(action = routes.Application.newPaper()) {
#inputText(paperForm("title"))
#******* Indexed chekbox name *********#
#for((t, index) <- topics.zipWithIndex) {
<input type="checkbox" name="topics[#index]" value="#t">#t <br>
}
<input type="submit" value="Create">
}
2. Then in your controller, as an action to handle form submit, you should doing something like this :
public static Result newPaper() {
// Bind submitted form value to your model, ex. Paper.java
Form<Paper> paperForm = Form.form(Paper.class).bindFromRequest();
Paper paper = paperForm.get();
Logger.info("Title entered = " + paper.title);
// Because in template we use indexed name, unchecked item are binded with null value
paper.topics.removeAll(Collections.singleton(null)); // remove value for unchecked topic
for (String t : paper.topics) {
Logger.info("The topic is " + t);
}
Logger.info("Total topic selected = " + paper.topics.size());
return redirect(routes.Application.index()); // redirect page
}
UPDATE
This is another idea to the solution. Your checkbox code on scala template is not modified.
#for(t <- topics) {
<input type='checkbox' name='topic' value=#t>#t <br>
}
So the controller should be like this :
public static Result newPaper() {
// Bind submitted form value to your model, ex. Paper.java
Form<Paper> paperForm = Form.form(Paper.class).bindFromRequest();
Paper paper = paperForm.get();
// get request value from submitted form
Map<String, String[]> map = request().body().asFormUrlEncoded();
String[] checkedVal = map.get("topic"); // get selected topics
// assign checked value to model
paper.topics = Arrays.asList(checkedVal);
// for debugging purpose
for (String t : paper.topics) {
Logger.info("The topic is " + t);
}
Logger.info("Total topic selected = " + paper.topics.size());
return redirect(routes.Application.index()); // redirect page
}
Hope this idea is more elegant.. :)
Note: I have tested on Play!Framework 2.1.1 too, and that is work for me.