文件上传进行封装

BaseServlet.javaif(isMultipart){ //如果是上传文件request = new MultipartRequestWrapper(request);}MultipartRequestWrapper.javapackage cn.com.leadfar.cms.backend.view;import java.io.FileOutputStream;import java.io.InputStream;import java.util.Arrays;import java.util.Date;import java.util.HashMap;import java.util.Map;import javax.servlet.http.HttpServletRequest;import javax.servlet.http.HttpServletRequestWrapper;import org.apache.commons.fileupload.FileItemIterator;import org.apache.commons.fileupload.FileItemStream;import org.apache.commons.fileupload.servlet.ServletFileUpload;import org.apache.commons.fileupload.util.Streams;import org.apache.commons.io.FilenameUtils;import cn.com.leadfar.cms.backend.model.Attachment;public class MultipartRequestWrapper extends HttpServletRequestWrapper {private Map allParams;public MultipartRequestWrapper(HttpServletRequest request) {super(request);//首先判断是否multipart编码类型//如果是multipart编码类型，就逐个从request中取出各个表单域//如果表单域是普通的表单域，则将它的值取出，放到allParams中//如果表单域是文件，则//1、把文件先存储到磁盘的某个目录中！//2、把文件的有关信息（名称，类型，上传时间）包装成Attachment[]类型//3、把包装好的Attachment[]类型，放到allParams中try {//首先，判断是否multipart编码类型boolean isMultipart = ServletFileUpload.isMultipartContent(request);if(!isMultipart){allParams = request.getParameterMap();}else{allParams = new HashMap();ServletFileUpload upload = new ServletFileUpload();FileItemIterator iter = upload.getItemIterator(request);while(iter.hasNext()){FileItemStream item = iter.next();//得到表单域的名称    String name = item.getFieldName();    //得到表单域的值（这是一个输入流）    InputStream stream = item.openStream();        //如果是普通表单域    if(item.isFormField()){    String value = Streams.asString(stream,request.getCharacterEncoding());    addFieldsAndValuesToMap(name, value);    }else{ //如果是文件    if(stream.available() != 0){//如果文件域没有选择文件，则忽略处理    String filename = item.getName(); //得到上传的文件名称    if(filename != null){    //因为在IE下面，上传的文件还包含有此文件在客户端机器的路径    //所以，要把这个路径去掉，只取文件名    filename = FilenameUtils.getName(filename);    }    //将上传文件的输入流输出到磁盘的文件上    Streams.copy(stream, new FileOutputStream(Attachment.ATTACHMENT_DIR+filename), true);        Attachment attachment = new Attachment();    attachment.setContentType(item.getContentType());    attachment.setName(filename);    attachment.setUploadTime(new Date());    addFieldsAndValuesToMap(name, attachment);    }    }}}} catch (Exception e) {e.printStackTrace();}}private void addFieldsAndValuesToMap(String name,String value){String[] fieldValues = (String[])allParams.get(name);if(fieldValues == null){allParams.put(name, new String[]{value});}else{//比如原来数组：["1","2"]//扩充之后：["1","2",null]fieldValues = Arrays.copyOf(fieldValues, fieldValues.length+1);fieldValues[fieldValues.length - 1] = value;allParams.put(name, fieldValues);}}private void addFieldsAndValuesToMap(String name,Attachment value){Attachment[] fieldValues = (Attachment[])allParams.get(name);if(fieldValues == null){allParams.put(name, new Attachment[]{value});}else{//比如原来数组：["1","2"]//扩充之后：["1","2",null]fieldValues = Arrays.copyOf(fieldValues, fieldValues.length+1);fieldValues[fieldValues.length - 1] = value;allParams.put(name, fieldValues);}}@Overridepublic String getParameter(String name) {String[] values = (String[])allParams.get(name);if(values != null){return values[0];}return null;}@Overridepublic Map getParameterMap() {return allParams;}}

?