我需要帮助在 JSF 页面中实现文件下载。到目前为止，我设法创建了这个：
<?xml version='1.0' encoding='UTF-8' ?>
<!DOCTYPE html PUBLIC "-//W3C//DTD XHTML 1.0 Strict//EN" "http://www.w3.org/TR/xhtml1/DTD/xhtml1-strict.dtd">
<html xmlns="http://www.w3.org/1999/xhtml" xml:lang="en" lang="en"
xmlns:h="http://java.sun.com/jsf/html"
xmlns:f="http://java.sun.com/jsf/core"
xmlns:ui="http://java.sun.com/jsf/facelets"
xmlns:p="http://primefaces.org/ui">
<h:head>
<ui:insert name="header">
<ui:include src="header.xhtml"/>
</ui:insert>
</h:head>
<h:body>
<h1><img src="resources/css/images/icon.png" alt="DX-57" /> Settings Center</h1>
<!-- layer for black background of the buttons -->
<div id="toolbar" style="margin: 0 auto; width:100%; height:30px; position:relative; background-color:black">
<!-- Include page Navigation -->
<ui:insert name="Navigation">
<ui:include src="Navigation.xhtml"/>
</ui:insert>
</div>
<div id="logodiv" style="position:relative; top:35px; left:0px;">
<h:graphicImage alt="Glassfish" style="position:relative" value="resources/images/logo_glassfish_settings.png" />
</div>
<div id="main" style="margin: 0 auto; width:1190px; height:700px; position:absolute; background-color:transparent; top:105px">
<div id="mainpage" style="margin: 0 auto; width:1190px; height:500px; position:absolute; background-color:transparent; top:80px">
<div id="settingsdiv" style="width:350px; height:400px; position:absolute; background-color:r; top:20px; left:1px">
<div id="settingsHashMap" style="width:1050px; height:400px; position:absolute; background-color:r; top:20px; left:1px">
<h:form id="form" >
<p:growl id="growl" showDetail="true" sticky="true" />
<!-- The sortable data table -->
<h:dataTable onmouseover="addOnclickToDatatableRows();" id="dataTable" headerClass="columnHeader" value="#{GlassfishController.dataList}" binding="#{table}" var="item">
<!-- Check box -->
<h:column>
<f:facet name="header">
<h:selectBooleanCheckbox style="margin-left: 0px;" value="#{GlassfishController.mainSelectAll}" class="checkall" >
<f:ajax listener="#{GlassfishController.selectAll}" render="@form" />
</h:selectBooleanCheckbox>
</f:facet>
<h:selectBooleanCheckbox onclick="highlight(this)" value="#{GlassfishController.selectedIds[item.filename]}" >
<!-- if the user deselects one row deselect the main checkbox -->
<f:ajax listener="#{GlassfishController.deselectMain}" render="@form" />
</h:selectBooleanCheckbox>
<!-- Click on table code -->
<h:outputLink id="lnkHidden" onclick="document.getElementById('form:btnHello').click(); return false;" style="text-decoration:none; color:white; background-color:black">
</h:outputLink>
</h:column>
<!-- Row number -->
<h:column>
<f:facet name="header">
<h:outputText value="№" />
</f:facet>
<h:outputText value="#{table.rowIndex + GlassfishController.firstRow + 1}" />
</h:column>
<h:column>
<f:facet name="header">
<h:commandLink value="File Name" actionListener="#{GlassfishController.sort}" style="text-decoration:none; color:white; background-color:black">
<f:attribute name="sortField" value="filename" />
<f:ajax render="@form" />
</h:commandLink>
</f:facet>
<h:outputText value="#{item.filename}" />
</h:column>
<h:column>
<f:facet name="header">
<h:commandLink value="Size" actionListener="#{GlassfishController.sort}" style="text-decoration:none; color:white; background-color:black">
<f:attribute name="sortField" value="size" />
<f:ajax render="@form" />
</h:commandLink>
</f:facet>
<h:outputText value="#{item.size} bytes" />
</h:column>
</h:dataTable>
<!-- The paging buttons -->
<h:commandButton value="first" action="#{GlassfishController.pageFirst}"
disabled="#{GlassfishController.firstRow == 0}" >
<f:ajax render="@form" execute="@form"></f:ajax>
</h:commandButton>
<h:commandButton value="prev" action="#{GlassfishController.pagePrevious}"
disabled="#{GlassfishController.firstRow == 0}" >
<f:ajax render="@form" execute="@form"></f:ajax>
</h:commandButton>
<h:commandButton value="next" action="#{GlassfishController.pageNext}"
disabled="#{GlassfishController.firstRow + GlassfishController.rowsPerPage >= GlassfishController.totalRows}" >
<f:ajax render="@form" execute="@form"></f:ajax>
</h:commandButton>
<h:commandButton value="last" action="#{GlassfishController.pageLast}"
disabled="#{GlassfishController.firstRow + GlassfishController.rowsPerPage >= GlassfishController.totalRows}" >
<f:ajax render="@form" execute="@form"></f:ajax>
</h:commandButton>
<h:outputText value="Page #{GlassfishController.currentPage} / #{GlassfishController.totalPages}" />
<br />
<!-- The paging links -->
<ui:repeat value="#{GlassfishController.pages}" var="page">
<h:commandLink value="#{page}" actionListener="#{GlassfishController.page}"
rendered="#{page != GlassfishController.currentPage}" style="text-decoration:none;color:white;">
<f:ajax render="@form" execute="@form"></f:ajax>
</h:commandLink>
<h:outputText value="#{page}" escape="false"
rendered="#{page == GlassfishController.currentPage}" style="text-decoration:none;color:gray;"/>
</ui:repeat>
<br />
<!-- Set rows per page -->
<h:outputLabel for="rowsPerPage" value="Rows per page" />
<h:inputText id="rowsPerPage" value="#{GlassfishController.rowsPerPage}" size="3" maxlength="3" />
<h:commandButton value="Set" action="#{GlassfishController.pageFirst}" >
<f:ajax render="@form" execute="@form"></f:ajax>
</h:commandButton>
<h:message for="rowsPerPage" errorStyle="color: red;" />
<!-- hidden button -->
<h:commandButton id="deleterow" value="HiddenDelete" action="#{GlassfishController.deleteSelectedIDs}" style="display:none">
<f:ajax render="@form"></f:ajax>
</h:commandButton>
<!-- the delete button -->
<h:button value="Delete" onclick="deletedialog(this, 'Do you want to delete the selected rows?'); return false;" />
<script type="text/javascript" src="resources/js/tabs.js"></script>
<h:commandLink id="btnHello" value="Download Files"
action="#{GlassfishController.downloadFile}">
</h:commandLink>
</h:form>
</div>
</div>
</div>
</div>
</h:body>
</html>
// Execute the download procedure
public void executeDownload(String filename) throws IOException{
int DEFAULT_BUFFER_SIZE = 10240;
String filePath = "/opt/glassfish3/glassfish/domains/domain1/logs/" + filename;
FacesContext context = FacesContext.getCurrentInstance();
HttpServletResponse response = (HttpServletResponse) context.getExternalContext().getResponse();
File file = new File(filePath);
if (!file.exists())
{
response.sendError(HttpServletResponse.SC_NOT_FOUND);
return;
}
response.reset();
response.setBufferSize(DEFAULT_BUFFER_SIZE);
response.setContentType("text");
response.setHeader("Content-Length", String.valueOf(file.length()));
response.setHeader("Content-Disposition", "attachment;filename=\""
+ file.getName() + "\"");
BufferedInputStream input = null;
BufferedOutputStream output = null;
try
{
input = new BufferedInputStream(new FileInputStream(file),
DEFAULT_BUFFER_SIZE);
output = new BufferedOutputStream(response.getOutputStream(),
DEFAULT_BUFFER_SIZE);
byte[] buffer = new byte[DEFAULT_BUFFER_SIZE];
int length;
while ((length = input.read(buffer)) > 0)
{
output.write(buffer, 0, length);
}
}
finally
{
input.close();
output.close();
}
context.responseComplete();
}
有一个我无法解决的问题，我需要帮助。当我单击下载按钮时，我可以成功下载日志文件。单击文件时，我想将文件下载到 JSF 表中。你能帮我实现它吗？或者你能给我一些建议吗？
最好的祝愿