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In Spring MVC Web apps, there might be multiple combination between Controller, JSP(View), and Object class(Model). In other words, almost any combination is possible.
It is a lot more flexible compared to Struts which tied one Action class (controller class) tied with Form class (object model class).
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There are number of Controller, Model classes, and views (JSP) in one Web App, and this examples shows the screen transition involved between two controllers and views (JSP).
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Summarized as four steps:
- First Controller calls the first JSP.
- First JSP calls the second Controller.
- Second Controller calls the second JSP.
- Second JSP is initialized.
Step 1 to 2. The first Controller (RmaController.java) calls main_01.jsp.
Step 2 to 3. The main_01.jsp calls second controller RmaDtlController.java.
Step 4. The second JSP (sub_line_01.jsp) is initialized.
Again (1 to 2), the first controller (RmaController.java) is invoked by a link, and calls second controller (RmaDtlController.java).
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Let’s look at step (2 to 3):
The main_01.jsp calls second controller RmaDtlController.java once the link is clicked (line 16).
<c:forEach items="${HDR_LIST}" var="rmaObj" varStatus="loop">
<tr height="15">
<td><form:radiobutton path="radioBtn" class='close clickIdx' data-id='${rmaObj.id}' /></td>
<td><form:checkbox path="selectedCheckBox" value="${rmaObj.rmaNum}"/></td>
<td id="id${loop.index}">${rmaObj.id}</td>
<td id="idRmaNum${loop.index}">${rmaObj.rmaNum}</td>
<td id="idStsCd${loop.index}">${rmaObj.rmaHdrStsCd}</td>
<td id="idStsNm${loop.index}">${rmaObj.rmaHdrStsNm}</td>
<td id="idTpCd${loop.index}">${rmaObj.rtrnTpCd}</td>
<td id="idTpNm${loop.index}">${rmaObj.rtrnTpNm}</td>
<td id="idRsnCd${loop.index}">${rmaObj.rtrnRsnCd}</td>
<td id="idRsnNm${loop.index}">${rmaObj.rtrnRsnNm}</td>
<td id="idCustCd${loop.index}">${rmaObj.sellToCustCd}</td>
<td><a href="<c:url value='/edit/${rmaObj.id}' />" >Edit</a></td>
<td><a href="<c:url value='/remove/${rmaObj.id}' />" >Delete</a></td>
<td><a href="<c:url value='/cUrlValSubLine01Jsp/${rmaObj.rmaNum}' />" >Detail</a></td>
</tr>
</c:forEach>
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In the line 16:
2.1. Link clicked contains an ID (RMA000016)
2.2. “cUrlValSubLine01Jsp” specified in second JSP (sub_line_01.jsp) and it will be called
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2.3. The URL for second JSP: http://localhost:8080/NS2015V07/cUrlValSubLine01Jsp/RMA000016
Step 3: Second Controller calls the second JSP.
@RequestMapping("/cUrlValSubLine01Jsp/{rmaNum}")
public ModelAndView goToSubLine01Jsp(@PathVariable("rmaNum") String rmaNum, Model model, HttpServletRequest req) {
List<RmaLineModel> rmaLineModelList = RmaDtlBL.getRmaLineListWithCdTblNm(rmaNum, null);
return getMVSubLine01(rmaNum, rmaLineModelList, req);
}
3.1. Returns ModelAndView object
private ModelAndView getMVSubLine01(String rmaNum, List<RmaLineModel> rmaLinsList, HttpServletRequest req) {
RmaLineListModel newModel = new RmaLineListModel(rmaNum, rmaLinsList);
ModelAndView modelAndView = new ModelAndView(VIEW.SUB_LINE_01.getVal());
modelAndView.addObject(CONST.FORM_KEY.getVal(), newModel);
// For item detail list
modelAndView.addObject(CONST.LINE_LIST_MODEL.getVal(), newModel);
// Setup Status drop down line the item list
modelAndView.addObject(CONST.HDR_STS_LIST.getVal(), getList(CONST.HDR_STS_LIST.getVal()));
// Item list for AJAX Auto complete
req.getSession().setAttribute(CONST.MDSE_LIST.getVal(), getList(CONST.MDSE_LIST.getVal()));
return modelAndView;
}
In the line 5:
3.2. Get the view name (“sub_line_01”) as constant (below) and set it to the object
enum VIEW {
MAIN_01("main_01"),
SUB_LINE_01("sub_line_01"),
SUB_TP_01("sub_tp_01"),
SUB_RSN_01("sub_rsn_01"),
SUB_TP_RSN_01("sub_tp_rsn_01"),
REDIRECT_HOME("redirect:/ns-home")
;
private String code;
VIEW(String code) {
this.code = code;
}
public String getVal() {
return code;
}
}
Step 4: Second JSP is initialized.
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