Tomcat Multipart类型参数处理

private void parseParts(boolean explicit) {if (this.parts == null && this.partsParseException == null) {        Context context = this.getContext();        MultipartConfigElement mce = this.getWrapper().getMultipartConfigElement();if (mce == null) {if (!context.getAllowCasualMultipartParsing()) {if (explicit) {this.partsParseException = new IllegalStateException(sm.getString("coyoteRequest.noMultipartConfig"));return;                }this.parts = Collections.emptyList();return;            }            mce = new MultipartConfigElement((String)null, (long)this.connector.getMaxPostSize(), (long)this.connector.getMaxPostSize(), this.connector.getMaxPostSize());        }        int maxParameterCount = this.getConnector().getMaxParameterCount();        Parameters parameters = this.coyoteRequest.getParameters();        parameters.setLimit(maxParameterCount);        boolean success = false;try {// 获取临时目录,用于存放参数临时文件及其对应值            String locationStr = mce.getLocation();            File location;if (locationStr != null && locationStr.length() != 0) {                location = new File(locationStr);if (!location.isAbsolute()) {                    location = (new File((File)context.getServletContext().getAttribute("javax.servlet.context.tempdir"), locationStr)).getAbsoluteFile();                }            } else {                location = (File)context.getServletContext().getAttribute("javax.servlet.context.tempdir");            }if (!location.exists() && context.getCreateUploadTargets()) {                log.warn(sm.getString("coyoteRequest.uploadCreate", new Object[]{location.getAbsolutePath(), this.getMappingData().wrapper.getName()}));if (!location.mkdirs()) {                    log.warn(sm.getString("coyoteRequest.uploadCreateFail", new Object[]{location.getAbsolutePath()}));                }            }if (location.isDirectory()) {                DiskFileItemFactory factory = new DiskFileItemFactory();try {                    factory.setRepository(location.getCanonicalFile());                } catch (IOException var34) {                    IOException ioe = var34;                    parameters.setParseFailedReason(FailReason.IO_ERROR);this.partsParseException = ioe;return;                }                factory.setSizeThreshold(mce.getFileSizeThreshold());                ServletFileUpload upload = new ServletFileUpload();                upload.setFileItemFactory(factory);                upload.setFileSizeMax(mce.getMaxFileSize());                upload.setSizeMax(mce.getMaxRequestSize());if (maxParameterCount > -1) {                    upload.setFileCountMax((long)(maxParameterCount - parameters.size()));                }this.parts = new ArrayList();try {// 关键在此处，解析multipart请求，内部会对请求的每个参数在临时目录生成一个临时文件内容为该参数的值                    List<FileItem> items = upload.parseRequest(new ServletRequestContext(this));                    int maxPostSize = this.getConnector().getMaxPostSize();                    int postSize = 0;                    Charset charset = this.getCharset();                    Iterator var15 = items.iterator();while(var15.hasNext()) {                        FileItem item = (FileItem)var15.next();                        ApplicationPart part = new ApplicationPart(item, location);this.parts.add(part);if (part.getSubmittedFileName() == null) {                            String name = part.getName();if (maxPostSize >= 0) {                                postSize += name.getBytes(charset).length;                                ++postSize;                                postSize = (int)((long)postSize + part.getSize());                                ++postSize;if (postSize > maxPostSize) {                                    parameters.setParseFailedReason(FailReason.POST_TOO_LARGE);throw new IllegalStateException(sm.getString("coyoteRequest.maxPostSizeExceeded"));                                }                            }                            String value = null;try {                                value = part.getString(charset.name());                            } catch (UnsupportedEncodingException var29) {                            }                            parameters.addParameter(name, value);                        }                    }                    success = true;                } catch (InvalidContentTypeException var30) {                    parameters.setParseFailedReason(FailReason.INVALID_CONTENT_TYPE);this.partsParseException = new ServletException(var30);                } catch (SizeException var31) {                    parameters.setParseFailedReason(FailReason.POST_TOO_LARGE);this.checkSwallowInput();this.partsParseException = new IllegalStateException(var31);                } catch (IOException var32) {                    parameters.setParseFailedReason(FailReason.IO_ERROR);this.partsParseException = new IOException(var32);                } catch (IllegalStateException var33) {                    IllegalStateException e = var33;this.checkSwallowInput();this.partsParseException = e;                }return;            }            parameters.setParseFailedReason(FailReason.MULTIPART_CONFIG_INVALID);this.partsParseException = new IOException(sm.getString("coyoteRequest.uploadLocationInvalid", new Object[]{location}));        } finally {if (this.partsParseException != null || !success) {                parameters.setParseFailedReason(FailReason.UNKNOWN);            }        }    }}

public List<FileItem> parseRequest(RequestContext ctx) throws FileUploadException {    List<FileItem> items = new ArrayList();    boolean successful = false;    boolean var22 = false;    ArrayList var32;    FileItem fileItem;try {        var22 = true;// 解析获取Multipart中所有参数条目        FileItemIterator iter = this.getItemIterator(ctx);        FileItemFactory fileItemFactory = (FileItemFactory)Objects.requireNonNull(this.getFileItemFactory(), "No FileItemFactory has been set.");        byte[] buffer = new byte[8192];// 循环迭代为每个参数Item创建一个临时文件并调用Streams.copy将这个参数的请求值拷贝到这个临时文件中。while(true) {if (!iter.hasNext()) {                successful = true;                var32 = items;                var22 = false;break;            }if ((long)items.size() == this.fileCountMax) {throw new FileCountLimitExceededException("attachment", this.getFileCountMax());            }            FileItemStream item = iter.next();            String fileName = item.getName();            fileItem = fileItemFactory.createItem(item.getFieldName(), item.getContentType(), item.isFormField(), fileName);            items.add(fileItem);try {                Streams.copy(item.openStream(), fileItem.getOutputStream(), true, buffer);            } catch (FileUploadIOException var25) {                FileUploadIOException e = var25;throw (FileUploadException)e.getCause();            } catch (IOException var26) {                IOException e = var26;throw new IOFileUploadException(String.format("Processing of %s request failed. %s", "multipart/form-data", e.getMessage()), e);            }            FileItemHeaders fih = item.getHeaders();            fileItem.setHeaders(fih);        }    } catch (FileUploadException var27) {        FileUploadException e = var27;throw e;    } catch (IOException var28) {        IOException e = var28;throw new FileUploadException(e.getMessage(), e);    } finally {if (var22) {if (!successful) {                Iterator var12 = items.iterator();while(var12.hasNext()) {                    FileItem fileItem = (FileItem)var12.next();try {                        fileItem.delete();                    } catch (Exception var23) {                    }                }            }        }    }if (!successful) {        Iterator var33 = items.iterator();while(var33.hasNext()) {            fileItem = (FileItem)var33.next();try {                fileItem.delete();            } catch (Exception var24) {            }        }    }return var32;}org.apache.tomcat.util.http.fileupload.disk.DiskFileItemFactory#createItempublic FileItem createItem(String fieldName, String contentType, boolean isFormField, String fileName) {    DiskFileItem result = new DiskFileItem(fieldName, contentType, isFormField, fileName, this.sizeThreshold, this.repository);    result.setDefaultCharset(this.defaultCharset);return result;}org.apache.tomcat.util.http.fileupload.disk.DiskFileItem#getOutputStreampublic OutputStream getOutputStream() {if (this.dfos == null) {        File outputFile = this.getTempFile();this.dfos = new DeferredFileOutputStream(this.sizeThreshold, outputFile);    }returnthis.dfos;}org.apache.tomcat.util.http.fileupload.disk.DiskFileItem#getTempFileprotected File getTempFile() {if (this.tempFile == null) {        File tempDir = this.repository;if (tempDir == null) {            tempDir = new File(System.getProperty("java.io.tmpdir"));        }        String tempFileName = String.format("upload_%s_%s.tmp", UID, getUniqueId());this.tempFile = new File(tempDir, tempFileName);    }returnthis.tempFile;}org.apache.tomcat.util.http.fileupload.disk.DiskFileItem#getUniqueIdprivate static String getUniqueId() {    int limit = 100000000;    int current = COUNTER.getAndIncrement();    String id = Integer.toString(current);if (current < 100000000) {        id = ("00000000" + id).substring(id.length());    }return id;}

delete:426, DiskFileItem (org.apache.tomcat.util.http.fileupload.disk)delete:53, ApplicationPart (org.apache.catalina.core)cleanupMultipart:134, StandardServletMultipartResolver (org.springframework.web.multipart.support)cleanupMultipart:1251, DispatcherServlet (org.springframework.web.servlet)doDispatch:1108, DispatcherServlet (org.springframework.web.servlet)doService:965, DispatcherServlet (org.springframework.web.servlet)processRequest:1006, FrameworkServlet (org.springframework.web.servlet)doPost:909, FrameworkServlet (org.springframework.web.servlet)service:555, HttpServlet (javax.servlet.http)service:883, FrameworkServlet (org.springframework.web.servlet)service:623, HttpServlet (javax.servlet.http)internalDoFilter:209, ApplicationFilterChain (org.apache.catalina.core)doFilter:153, ApplicationFilterChain (org.apache.catalina.core)doFilter:51, WsFilter (org.apache.tomcat.websocket.server)internalDoFilter:178, ApplicationFilterChain (org.apache.catalina.core)doFilter:153, ApplicationFilterChain (org.apache.catalina.core)doFilterInternal:28, SecurityFilter (com.ar3h.postgresqljdbcattack.filter)doFilter:117, OncePerRequestFilter (org.springframework.web.filter)internalDoFilter:178, ApplicationFilterChain (org.apache.catalina.core)doFilter:153, ApplicationFilterChain (org.apache.catalina.core)doFilterInternal:100, RequestContextFilter (org.springframework.web.filter)doFilter:117, OncePerRequestFilter (org.springframework.web.filter)internalDoFilter:178, ApplicationFilterChain (org.apache.catalina.core)doFilter:153, ApplicationFilterChain (org.apache.catalina.core)doFilterInternal:93, FormContentFilter (org.springframework.web.filter)doFilter:117, OncePerRequestFilter (org.springframework.web.filter)internalDoFilter:178, ApplicationFilterChain (org.apache.catalina.core)doFilter:153, ApplicationFilterChain (org.apache.catalina.core)doFilterInternal:201, CharacterEncodingFilter (org.springframework.web.filter)doFilter:117, OncePerRequestFilter (org.springframework.web.filter)internalDoFilter:178, ApplicationFilterChain (org.apache.catalina.core)doFilter:153, ApplicationFilterChain (org.apache.catalina.core)invoke:167, StandardWrapperValve (org.apache.catalina.core)invoke:90, StandardContextValve (org.apache.catalina.core)invoke:481, AuthenticatorBase (org.apache.catalina.authenticator)invoke:130, StandardHostValve (org.apache.catalina.core)invoke:93, ErrorReportValve (org.apache.catalina.valves)invoke:74, StandardEngineValve (org.apache.catalina.core)service:343, CoyoteAdapter (org.apache.catalina.connector)service:390, Http11Processor (org.apache.coyote.http11)process:63, AbstractProcessorLight (org.apache.coyote)process:926, AbstractProtocol$ConnectionHandler (org.apache.coyote)doRun:1791, NioEndpoint$SocketProcessor (org.apache.tomcat.util.net)run:52, SocketProcessorBase (org.apache.tomcat.util.net)runWorker:1191, ThreadPoolExecutor (org.apache.tomcat.util.threads)run:659, ThreadPoolExecutor$Worker (org.apache.tomcat.util.threads)run:61, TaskThread$WrappingRunnable (org.apache.tomcat.util.threads)run:750, Thread (java.lang)