各位：
最近再写转发的项目，在过滤器中进行转发。
下面是在对文件上传进行转发时出现的错误
从HttpServletRequest中获取文件：
Collection<Part> parts = request.getParts(); //出现问题的位置
MultiValueMap<String, Object> resultMap = new LinkedMultiValueMap<>();
Iterator<Part> iterator = parts.iterator();
while (iterator.hasNext()) {
Part part = iterator.next();
//参数名称
String name = part.getName();
//文件名称
String submittedFileName = part.getSubmittedFileName();
//文件流
InputStream inputStream = part.getInputStream();
}
后来用postman进行测试；测试10次，大概有4次左右会报错，每次报错都不一样：
下面是报错异常：
第一种：
报错位置：
Collection<Part> parts = request.getParts();
Caused by: java.nio.BufferUnderflowException
at java.nio.HeapByteBuffer.get(HeapByteBuffer.java:154)
at org.apache.catalina.connector.InputBuffer.read(InputBuffer.java:344)
at org.apache.catalina.connector.CoyoteInputStream.read(CoyoteInputStream.java:132)
at java.io.FilterInputStream.read(FilterInputStream.java:133)
at org.apache.tomcat.util.http.fileupload.util.LimitedInputStream.read(LimitedInputStream.java:132)
at org.apache.tomcat.util.http.fileupload.MultipartStream$ItemInputStream.makeAvailable(MultipartStream.java:975)
at org.apache.tomcat.util.http.fileupload.MultipartStream$ItemInputStream.read(MultipartStream.java:879)
at java.io.InputStream.read(InputStream.java:101)
at org.apache.tomcat.util.http.fileupload.util.Streams.copy(Streams.java:97)
at org.apache.tomcat.util.http.fileupload.util.Streams.copy(Streams.java:68)
at org.apache.tomcat.util.http.fileupload.MultipartStream.readBodyData(MultipartStream.java:572)
at org.apache.tomcat.util.http.fileupload.MultipartStream.discardBodyData(MultipartStream.java:596)
at org.apache.tomcat.util.http.fileupload.MultipartStream.skipPreamble(MultipartStream.java:614)
at org.apache.tomcat.util.http.fileupload.impl.FileItemIteratorImpl.findNextItem(FileItemIteratorImpl.java:228)
at org.apache.tomcat.util.http.fileupload.impl.FileItemIteratorImpl.<init>(FileItemIteratorImpl.java:142)
at org.apache.tomcat.util.http.fileupload.FileUploadBase.getItemIterator(FileUploadBase.java:252)
at org.apache.tomcat.util.http.fileupload.FileUploadBase.parseRequest(FileUploadBase.java:276)
at org.apache.catalina.connector.Request.parseParts(Request.java:2921)
at org.apache.catalina.connector.Request.getParts(Request.java:2823)
at org.apache.catalina.connector.RequestFacade.getParts(RequestFacade.java:1098)
at com.github.firefly.filter.FireflyFilter.uploadDispatch(FireflyFilter.java:206)
at com.github.firefly.filter.FireflyFilter.request(FireflyFilter.java:164)
at com.github.firefly.filter.FireflyFilter.lambda$doFilter$2(FireflyFilter.java:80)
at java.util.concurrent.FutureTask.run$$$capture(FutureTask.java:266)
at java.util.concurrent.FutureTask.run(FutureTask.java)
at java.util.concurrent.ThreadPoolExecutor.runWorker(ThreadPoolExecutor.java:1149)
at java.util.concurrent.ThreadPoolExecutor$Worker.run(ThreadPoolExecutor.java:624)
... 1 more
Suppressed: org.apache.tomcat.util.http.fileupload.MultipartStream$MalformedStreamException: Stream ended unexpectedly
at org.apache.tomcat.util.http.fileupload.MultipartStream$ItemInputStream.makeAvailable(MultipartStream.java:981)
at org.apache.tomcat.util.http.fileupload.MultipartStream$ItemInputStream.close(MultipartStream.java:919)
at org.apache.tomcat.util.http.fileupload.MultipartStream$ItemInputStream.close(MultipartStream.java:898)
at org.apache.tomcat.util.http.fileupload.util.Streams.copy(Streams.java:117)
... 19 more
第二种：
报错位置：
Part part = iterator.next();
Caused by: java.util.ConcurrentModificationException
at java.util.ArrayList$Itr.checkForComodification(ArrayList.java:911)
at java.util.ArrayList$Itr.next(ArrayList.java:861)
at com.github.firefly.filter.FireflyFilter.uploadDispatch(FireflyFilter.java:210)
at com.github.firefly.filter.FireflyFilter.request(FireflyFilter.java:164)
at com.github.firefly.filter.FireflyFilter.lambda$doFilter$2(FireflyFilter.java:80)
at java.util.concurrent.FutureTask.run$$$capture(FutureTask.java:266)
at java.util.concurrent.FutureTask.run(FutureTask.java)
at java.util.concurrent.ThreadPoolExecutor.runWorker(ThreadPoolExecutor.java:1149)
at java.util.concurrent.ThreadPoolExecutor$Worker.run(ThreadPoolExecutor.java:624)
... 1 more
希望各位能给些解决方案，或者建议！
request.getParts()判断它是否空，或者引号字符串之类的，然后再走下面吧？