Struts2 结合HttpClient 实现远程服务器文件下载

1.1、页面配置部分

<button id="download" class="button" onclick="window.location.href = 'downloadExample.action';return false;">下载模板</button>
<s:submit id="importButton" value="上传文件" theme="simple" cssClass="button"></s:submit>
<s:reset value="重置路径" theme="simple" cssClass="button" ></s:reset>

1.2、Struts2配置文件部分

<!--下载模板-->
<action name="downloadExample" class="com.web.action.file.ImportAction">
<param name="downFileName">文件下载.xls</param>
<result name="success" type="stream">
<param name="contentType">application/vnd.ms-excel</param>
<param name="contentDisposition">attachment;filename="${downloadName}"</param>
<param name="inputName">downloadFile</param>
<param name="bufferSize">4096</param>
</result>
</action>

1.3、Action层中获取远程服务器文件流程序部分

public class ImportAction{

private String downFileName;
private String downloadName;

IFileService fileService;

/**
* @param fileService the fileService to set
*/
public void setEztFileService(IFileService fileService) {
this.fileService = fileService;
}

/**
* @return the downFileName
*/
public String getDownFileName() {
return downFileName;
}

/**
* @param downFileName the downFileName to set
*/
public void setDownFileName(String downFileName) {
this.downFileName = downFileName;
}

/**
* @return the downloadName
*/
public String getDownloadName() {
return downloadName;
}

/**
* @param downloadName the downloadName to set
*/
public void setDownloadName(String downloadName) {
this.downloadName = downloadName;
}

public InputStream getDownloadFile(){
downloadName = fileService.getDownloadFileName(downFileName); //下载文件显示名称转编码
Properties properties = ResourceUtil.getProperties("file.properties");

//取得远程服务器信息配置属性文件file.properties文件为自定义文件放置在web项目src/conf文件夹下
String strRemoteFileUrl = properties.getProperty("serverPath")+ properties.getProperty("templateName"); //取得远程文件路径
InputStream in = fileService.getDownloadFile(strRemoteFileUrl); //调用Service层方法取得远程服务器文件流
return in;
}

}

1.4、Service层接口实现

public class FileService implements IFileService {

public String getDownloadFileName(String downFileName) { //解决下载文件名称中文乱码问题
try {
downFileName = new String(downFileName.getBytes(), "ISO-8859-1");
} catch (UnsupportedEncodingException e) {
e.printStackTrace();
}
return downFileName;
}

public InputStream getDownloadFile(String strRemoteFileUrl) {
// TODO Auto-generated method stub
HttpClient client = new HttpClient();
GetMethod httpGet = new GetMethod(strRemoteFileUrl);
InputStream in = null;
try {
int intResponseCode = client.executeMethod(httpGet);
in = httpGet.getResponseBodyAsStream();
} catch (HttpException e) {
// TODO Auto-generated catch block

//记录日志
} catch (IOException e) {
// TODO Auto-generated catch block

//记录日志
}
return in;
}

}

1.5、读取properties文件工具类部分

public class ResourceUtil {
public static Properties getProperties(String fileName) {
try {
Properties properties = new Properties();
ClassLoader cl = Thread.currentThread().getContextClassLoader();
properties.load(cl.getResourceAsStream(fileName));
return properties;
} catch (Exception ex) {
ex.printStackTrace();
}
return null;
}

}

1.6、总结：此项实现，在文件服务器运行正常的情况下文件下载正常，如果文件服务器运行异常或已停止运行则在jsp页面部分将会抛出异常。

2.1、页面配置部分

<div><font color="#FF0000">${meg}</font></div>

<button id="download" class="button" onclick="window.location.href = 'downloadExample.action';return false;">下载模板</button>
<s:submit id="importButton" value="上传文件" theme="simple" cssClass="button"></s:submit>
<s:reset value="重置路径" theme="simple" cssClass="button" ></s:reset>

2.2、Struts2配置文件部分

<!--下载模板-->
<action name="downloadExample" class="com.web.action.file.ImportAction">
<param name="downFileName">文件下载.xls</param>
<result name="success" type="stream">
<param name="contentType">application/vnd.ms-excel</param>
<param name="contentDisposition">attachment;filename="${downloadName}"</param>
<param name="inputName">downloadFile</param>
<param name="bufferSize">4096</param>
</result>

<result name="error">/com/import/download.jsp</result>
</action>

2.3、Action层中获取远程服务器文件流程序部分

public class ImportAction{

private String downFileName;
private String downloadName;

private InputStream downloadFile;

IFileService fileService;

/**
* @param fileService the fileService to set
*/
public void setEztFileService(IFileService fileService) {
this.fileService = fileService;
}

/**
* @return the downFileName
*/
public String getDownFileName() {
return downFileName;
}

/**
* @param downFileName the downFileName to set
*/
public void setDownFileName(String downFileName) {
this.downFileName = downFileName;
}

/**
* @return the downloadName
*/
public String getDownloadName() {
return downloadName;
}

/**
* @param downloadName the downloadName to set
*/
public void setDownloadName(String downloadName) {
this.downloadName = downloadName;
}

/**
* @return the downloadFile
*/
public InputStream getDownloadFile() {
return downloadFile;
}

/**
* @param downloadFile the downloadFile to set
*/
public void setDownloadFile(InputStream downloadFile) {
this.downloadFile = downloadFile;
}

public InputStream getDownloadFile(){
downloadName = fileService.getDownloadFileName(downFileName); //下载文件显示名称转编码
Properties properties = ResourceUtil.getProperties("file.properties");

//取得远程服务器信息配置属性文件file.properties文件为自定义文件放置在web项目src/conf文件夹下
String strRemoteFileUrl = properties.getProperty("serverPath")+ properties.getProperty("templateName"); //取得远程文件路径
downloadFile = fileService.getDownloadFile(strRemoteFileUrl); //调用Service层方法取得远程服务器文件流变量名称与配置文件相符
if (null==downloadFile) {
request.setAttribute("meg", "模板下载异常！");
return ERROR;
} else {
return SUCCESS;
}
}

}

2.4、Service层接口实现

public class FileService implements IFileService {

public String getDownloadFileName(String downFileName) { //解决下载文件名称中文乱码问题
try {
downFileName = new String(downFileName.getBytes(), "ISO-8859-1");
} catch (UnsupportedEncodingException e) {
e.printStackTrace();
}
return downFileName;
}

public InputStream getDownloadFile(String strRemoteFileUrl) {
// TODO Auto-generated method stub
HttpClient client = new HttpClient();
GetMethod httpGet = new GetMethod(strRemoteFileUrl);
InputStream in = null;
try {
int intResponseCode = client.executeMethod(httpGet);
in = httpGet.getResponseBodyAsStream();
} catch (HttpException e) {
// TODO Auto-generated catch block

//记录日志
} catch (IOException e) {
// TODO Auto-generated catch block

//记录日志
}
return in;
}

}

2.5、读取properties文件工具类部分

public class ResourceUtil {
public static Properties getProperties(String fileName) {
try {
Properties properties = new Properties();
ClassLoader cl = Thread.currentThread().getContextClassLoader();
properties.load(cl.getResourceAsStream(fileName));
return properties;
} catch (Exception ex) {
ex.printStackTrace();
}
return null;
}

}

2.6、总结：此项实现，在文件服务器运行正常的情况下文件下载正常，如果文件服务器运行异常则将返回下载页面并提示异常信息。