如何用seam实现文件上传

1. 需要两个seam组件。一个Tomahawk 和SLSB用来处理JSF action 的 "backing bean"。

1a. Backing Bean:

@Name("uploadBean")
public class UploadBackingBean {

private UploadedFile file;

public void setFile(UploadedFile file) {
this.file = file;
}

@NotNull
public UploadedFile getFile() {
return this.file;
}

}

1b. Action 和它的接口文件

@Stateless
@Name("upload")
@Interceptors(SeamInterceptor.class)
public class UploadAction implements Upload {

private Logger logger;

/**
* O arquivo que foi enviado.
*/
@In
private UploadBackingBean uploadBean;

@In
private FacesContext facesContext;

@PostConstruct
public void init() {
logger = Logger.getLogger(this.getClass());
logger.debug("init()");
}

public String upload() {
logger.debug("upload()");
UploadedFile file = uploadBean.getFile();

logger.debug("Abrindo o arquivo como DOM4J");

logger.debug(file.getName());

facesContext.addMessage(null, new FacesMessage("Nome do arquivo: "
+ file.getName()));

return "success";
}

}

@Local
public interface Upload {

public String upload();

}

2. 如果你想通过facelets存取tomahawk upload 组件，需要定义一个tomahawk.taglib.xml 文件。它应被包含在.war 包的WEB-INF 目录。

<?xml version="1.0"?>
<!DOCTYPE facelet-taglib PUBLIC "-//Sun Microsystems, Inc.//DTD Facelet Taglib 1.0//EN" "facelet-taglib_1_0.dtd">
<facelet-taglib>
<!-- author: thomas.jachmann@mindmatters.de -->
<namespace>http://myfaces.apache.org/tomahawk</namespace>
<tag>
<tag-name>inputFileUpload</tag-name>
<component>
<component-type>org.apache.myfaces.HtmlInputFileUpload</component-type>
</component>
</tag>
</facelet-taglib>

完整的taglib 定义: http://wiki.apache.org/myfaces-data/attachments/Use_Facelets_with_Tomahawk/attachments/tomahawk.taglib.xml


3. web.xml中，Tomahawk 需要的部分：

<!-- My Faces Extensions Filter -->
<filter>
<filter-name>extensionsFilter</filter-name>
<filter-class>org.apache.myfaces.component.html.util.ExtensionsFilter</filter-class>
<init-param>
<param-name>uploadMaxFileSize</param-name>
<param-value>100m</param-value>
<!--
<description>Set the size limit for uploaded files.
Format: 10 - 10 bytes
10k - 10 KB
10m - 10 MB
1g - 1 GB
</description>
-->
</init-param>
<init-param>
<param-name>uploadThresholdSize</param-name>
<param-value>100k</param-value>
<!--
<description>Set the threshold size - files
below this limit are stored in memory, files above
this limit are stored on disk.

Format: 10 - 10 bytes
10k - 10 KB
10m - 10 MB
1g - 1 GB
</description>
-->
</init-param>
<!--
<init-param>
<param-name>uploadRepositoryPath</param-name>
<param-value>/temp</param-value>
<description>Set the path where the intermediary files will be stored.
</description>
</init-param>
-->
</filter>

<filter-mapping>
<filter-name>extensionsFilter</filter-name>
<url-pattern>*.seam</url-pattern>
</filter-mapping>

<!-- MyFaces Tomahawk Library -->

<context-param>
<param-name>facelets.LIBRARIES</param-name>
<param-value>/WEB-INF/tomahawk.taglib.xml</param-value>
</context-param>

4. HTML可以像这样：

<h:form enctype="multipart/form-data">
<t:inputFileUpload storage="file" value="#{uploadBean.file}"/>
<h:commandButton value="Submit" action="#{upload.upload}"/>
<h:messages/>
</h:form>

5. 最后，把tomahawk.jar 、the commons-file-upload.jar、common-io.jar 打包到ear。当然需要在MANIFEST.MF 文件中修改class-path。

Class-Path: jboss-seam.jar commons-fileupload-1.1.jar commons-io-1.2.jar tomahawk.jar

希望有所帮助. Regards. Marcio Endo

下面有附件。文件是fileupload.zip。它不包含完善的build.xml。不过你可以通过ant -f packaging-build.xml 生成必需的.ear。

例子运行环境：

JBoss-4.0.4.CR2

JBoss-Seam-1.0.0.CR2

MyFaces 1.1.1

Tomahawk 1.1.1

Marcio Endo

不必修改manifest 文件。我已经把全部tomahawk 组件集成了。一会儿我把设置贴出来。

Fady Matar

Alternative FileUpload
我已经集成了例子文件，不需要backing bean ，用seam gen工具建立项目。

Arthur Marinis

附件:

fileupload.zip

1849616 bytes

bq_cui:

这个例子我还没有测试，应该还不能将文件上传信息保存到数据库中。2007-4-27