使用Struts2上传图片

在Struts2中为我们提供了比较简单的文件上传方式.

首先引入commons-fileupload-x.jar、commons-io-x.jar 这两个jar包,然后引入Struts2相关jar包

 

接下来新建一个jsp文件:写一个文件上传表单,这里需要特别注意要在form加上enctype="multipart/form-data"  method="post" .

 

<form action="/admin/center/brandAction!addBrandProcess" enctype="multipart/form-data" method="post">
		<table width="90%" border="0" cellspacing="2" cellpadding="3"
			align="center">
			<tr bgcolor="f5f5f5">
				<td width="22%">
					<div align="right">图片：</div>
				</td>
				<td width="78%"><input type="file" name="uploadFile" />
				</td>
			</tr>
			<tr bgcolor="f5f5f5">
				<td colspan="2">
					<div align="center">
						<input type="submit" value=" 确 定 ">
					</div>
				</td>
			</tr>
		</table>
</form>

 

下一步:添加我们的Action类:

package gd.hz.shopping.action;

import java.io.File;
import java.io.IOException;
import java.text.SimpleDateFormat;
import java.util.Date;
import java.util.UUID;

import org.apache.commons.io.FileUtils;
import org.apache.struts2.ServletActionContext;
import org.springframework.context.annotation.Scope;
import org.springframework.stereotype.Controller;

import com.opensymphony.xwork2.ActionSupport;

@Controller("brandAction")
@Scope("prototype")
public class Test extends ActionSupport {

	private static final long serialVersionUID = 1L;
	
	//此属性对应于表单中文件字段的名称  
	private File uploadFile; 
    //下面的这两个属性的命名必须遵守上定的规则，即为"表单中文件字段的名称" + "相应的后缀"  
    private String uploadFileContentType; // 得到上传的文件的数据类型,  
    private String uploadFileFileName; // 得到上传的文件的名称  
	
	public File getUploadFile() {
		return uploadFile;
	}
	public void setUploadFile(File uploadFile) {
		this.uploadFile = uploadFile;
	}
	
	public String getUploadFileContentType() {
		return uploadFileContentType;
	}
	public void setUploadFileContentType(String uploadFileContentType) {
		this.uploadFileContentType = uploadFileContentType;
	}
	
	public String getUploadFileFileName() {
		return uploadFileFileName;
	}
	public void setUploadFileFileName(String uploadFileFileName) {
		this.uploadFileFileName = uploadFileFileName;
	}
	
	public String addBrandProcess() throws IOException
	{
		String realPath = ServletActionContext.getServletContext().getRealPath("/images");
		SimpleDateFormat date = new SimpleDateFormat("/yyyy/MM/dd");
		String dateTime = date.format(new Date());
		realPath += dateTime;
		
		uploadFileFileName = UUID.randomUUID().toString() + uploadFileFileName.substring(uploadFileFileName.lastIndexOf('.'));
		
		System.out.println(uploadFileContentType); 
		//控制图片类型
		if(uploadFileContentType.equals("image/gif") || uploadFileContentType.equals("image/jpeg") || 
				uploadFileContentType.equals("image/png") || uploadFileContentType.equals("image/bmp") || 
				uploadFileContentType.equals("image/x-icon") || uploadFileContentType.equals("image/pjpeg"))
		{
			//判断文件是否为空,并且文件不能大于2M
	        if(uploadFile != null && uploadFile.length() < 2097152)
	        {  
	        	//根据 parent 抽象路径名和 child 路径名字符串创建一个新 File 实例。
	            File filePath = new File(new File(realPath), uploadFileFileName);  
	            //判断路径是否存在  
	            if(!filePath.getParentFile().exists())
	            {
	            	//如果不存在，则递归创建此路径 
	            	filePath.getParentFile().mkdirs();
	            }
	            System.out.println(uploadFileFileName); 
	            System.out.println(filePath.getParentFile()); 
	            //将文件保存到硬盘上,Struts2会帮我们自动删除临时文件
	            try {
					FileUtils.copyFile(uploadFile, filePath);
				} catch (IOException e) {
					System.out.println("图片上传失败"); 
					e.printStackTrace();
				} 
	        }  
		}
		return "success";  
	}
}

 

上面还是要遵守约定大于配置,注意名称的命名,uploadFileContentType和uploadFileFileName必须遵守Struts2的规则.

 

Struts2默认文件的上传大小是2M,当大于2M时会抛出异常,这里我们可以在struts.xml文件里做如下配置,控制上传文件的大小:

<struts>  
<constant name="struts.multipart.maxSize" value="10485761"/>   
</struts>