基于HttpClient上传文件中文名乱码的解决基于HttpClient上传文件中文名乱

现象使用HttpClient工具上传文件时，如果文件名是中文，文件名会乱码
文件名乱码的代码：

private HttpEntity buildEntity(Long scenarioId, List groupIds, String extension,File fileToUpload) {MultipartEntityBuilder builder = MultipartEntityBuilder.create(); builder.addTextBody("scenarioId", scenarioId.toString()); for (String groupId : groupIds) {builder.addTextBody("groupIds", groupId); }builder.addTextBody("extension", extension); builder.addPart("fileToUpload", new FileBody(fileToUpload)); builder.addTextBody("type", AssetFileTypeEnum.CSV.getName()); builder.addTextBody("isSplit", "false"); builder.addTextBody("isRefresh", "false"); return builder.build();

乱码原因：

HttpClient上传文件时，会调用doWriteTo方法，写一个输出流，但是在调用formatMultipartHeader方法时，底层主要有3种不同的实现，3种方式的采用的字符集不一样

HttpClient中的doWriteTo方法：

void doWriteTo(final OutputStream out,final boolean writeContent) throws IOException {final ByteArrayBuffer boundaryEncoded = encode(this.charset, this.boundary); for (final FormBodyPart part: getBodyParts()) {writeBytes(TWO_DASHES, out); writeBytes(boundaryEncoded, out); writeBytes(CR_LF, out); //此处代码主要有3种不同的实现,不同的mode,实现方式不一样，采用的字符集也不同formatMultipartHeader(part, out); writeBytes(CR_LF, out); if (writeContent) {part.getBody().writeTo(out); }writeBytes(CR_LF, out); }writeBytes(TWO_DASHES, out); writeBytes(boundaryEncoded, out); writeBytes(TWO_DASHES, out); writeBytes(CR_LF, out); }

其中的formatMultipartHeader方法，不同的模式有不同的实现方式
MultipartEntityBuilder

MultipartFormEntity buildEntity() {String boundaryCopy = boundary; if (boundaryCopy == null && contentType != null) {boundaryCopy = contentType.getParameter("boundary"); }if (boundaryCopy == null) {boundaryCopy = generateBoundary(); }Charset charsetCopy = charset; if (charsetCopy == null && contentType != null) {charsetCopy = contentType.getCharset(); }final List paramsList = new ArrayList(2); paramsList.add(new BasicNameValuePair("boundary", boundaryCopy)); if (charsetCopy != null) {paramsList.add(new BasicNameValuePair("charset", charsetCopy.name())); }final NameValuePair[] params = paramsList.toArray(new NameValuePair[paramsList.size()]); final ContentType contentTypeCopy = contentType != null ?contentType.withParameters(params) :ContentType.create("multipart/" + DEFAULT_SUBTYPE, params); final List bodyPartsCopy = bodyParts != null ? new ArrayList(bodyParts) :Collections.emptyList(); //此处将mode赋值给modeCopyfinal HttpMultipartMode modeCopy = mode != null ? mode : HttpMultipartMode.STRICT; final AbstractMultipartForm form; //此处根据modeCopy的值不同，构造3种form，每种的字符集都不一样，也是产生乱码的根源switch (modeCopy) {case BROWSER_COMPATIBLE:form = new HttpBrowserCompatibleMultipart(charsetCopy, boundaryCopy, bodyPartsCopy); break; case RFC6532:form = new HttpRFC6532Multipart(charsetCopy, boundaryCopy, bodyPartsCopy); break; default:form = new HttpStrictMultipart(charsetCopy, boundaryCopy, bodyPartsCopy); }return new MultipartFormEntity(form, contentTypeCopy, form.getTotalLength()); }public HttpEntity build() {return buildEntity(); }

BROWSER_COMPATIBLE模式中的formatMultipartHeader方法

class HttpBrowserCompatibleMultipart extends AbstractMultipartForm {private final List parts; public HttpBrowserCompatibleMultipart(final Charset charset,final String boundary,final List parts) {super(charset, boundary); this.parts = parts; }@Overridepublic List getBodyParts() {return this.parts; }/*** Write the multipart header fields; depends on the style.*/@Overrideprotected void formatMultipartHeader(final FormBodyPart part,final OutputStream out) throws IOException {// For browser-compatible, only write Content-Disposition// Use content charsetfinal Header header = part.getHeader(); final MinimalField cd = header.getField(MIME.CONTENT_DISPOSITION); //可以看到此处的字符集采用的是设置的字符集writeField(cd, this.charset, out); final String filename = part.getBody().getFilename(); if (filename != null) {final MinimalField ct = header.getField(MIME.CONTENT_TYPE); //可以看到此处的字符集采用的也是设置的字符集writeField(ct, this.charset, out); }}}

RFC6532模式中的formatMultipartHeader方法

class HttpRFC6532Multipart extends AbstractMultipartForm {private final List parts; public HttpRFC6532Multipart(final Charset charset,final String boundary,final List parts) {super(charset, boundary); this.parts = parts; }@Overridepublic List getBodyParts() {return this.parts; }@Overrideprotected void formatMultipartHeader(final FormBodyPart part,final OutputStream out) throws IOException {// For RFC6532, we output all fields with UTF-8 encoding.final Header header = part.getHeader(); for (final MinimalField field: header) {//可以看到此处的字符集默认采用UTF8writeField(field, MIME.UTF8_CHARSET, out); }}}

默认模式中的formatMultipartHeader方法

class HttpStrictMultipart extends AbstractMultipartForm {private final List parts; public HttpStrictMultipart(final Charset charset,final String boundary,final List parts) {super(charset, boundary); this.parts = parts; }@Overridepublic List getBodyParts() {return this.parts; }@Overrideprotected void formatMultipartHeader(final FormBodyPart part,final OutputStream out) throws IOException {// For strict, we output all fields with MIME-standard encoding.//从上面注释中可以看到，此处的字符集采用的是默认字符集即ASCII（下面MIME类中可以看到）final Header header = part.getHeader(); for (final MinimalField field: header) {writeField(field, out); }}}

MIME类

public final class MIME {public static final String CONTENT_TYPE= "Content-Type"; public static final String CONTENT_TRANSFER_ENC= "Content-Transfer-Encoding"; public static final String CONTENT_DISPOSITION= "Content-Disposition"; public static final String ENC_8BIT= "8bit"; public static final String ENC_BINARY= "binary"; /** The default character set to be used, i.e. "US-ASCII" */public static final Charset DEFAULT_CHARSET= Consts.ASCII; /** UTF-8 is used for RFC6532 */public static final Charset UTF8_CHARSET= Consts.UTF_8; }

解决方法知道乱码产生的根源，乱码问题也就好解决了，解决方式有两种
设置mode为：BROWSER_COMPATIBLE，并设置字符集为UTF8

private HttpEntity buildEntity(Long scenarioId, List groupIds, String extension,File fileToUpload) {MultipartEntityBuilder builder = MultipartEntityBuilder.create(); //设置模式为BROWSER_COMPATIBLE，并设置字符集为UTF8builder.setMode(HttpMultipartMode.BROWSER_COMPATIBLE); builder.setCharset(Charset.forName("UTF-8")); builder.addTextBody("scenarioId", scenarioId.toString()); for (String groupId : groupIds) {builder.addTextBody("groupIds", groupId); }builder.addTextBody("extension", extension); builder.addPart("fileToUpload", new FileBody(fileToUpload)); builder.addTextBody("type", AssetFileTypeEnum.CSV.getName()); builder.addTextBody("isSplit", "false"); builder.addTextBody("isRefresh", "false"); return builder.build(); }

设置模式为：RFC6532

private HttpEntity buildEntity(Long scenarioId, List groupIds, String extension,File fileToUpload) {MultipartEntityBuilder builder = MultipartEntityBuilder.create(); //设置模式为RFC6532builder.setMode(HttpMultipartMode.RFC6532); builder.addTextBody("scenarioId", scenarioId.toString()); for (String groupId : groupIds) {builder.addTextBody("groupIds", groupId); }builder.addTextBody("extension", extension); builder.addPart("fileToUpload", new FileBody(fileToUpload)); builder.addTextBody("type", AssetFileTypeEnum.CSV.getName()); builder.addTextBody("isSplit", "false"); builder.addTextBody("isRefresh", "false"); return builder.build(); }

【基于HttpClient上传文件中文名乱码的解决】以上为个人经验，希望能给大家一个参考，也希望大家多多支持脚本之家。