BAEL-4860: Java IllegalStateException: "getInputStream() has already been called for this request" (#14121)

* [BAEL-6203] Deserialize Generic Type with Jackson * BAEL-4860: Java IllegalStateException: "getInputStream() has already been called for this request" * BAEL-4860: Move code to new module spring-web-module/spring-mvc-java-3. * BAEL-4860: update pom * BAEL-4860: make the test methods public
2023-06-12 11:49:15 +08:00
parent 680ddfef9c
commit 643f99281f
5 changed files with 112 additions and 0 deletions
@@ -0,0 +1,23 @@
+package com.baeldung.filters;
+
+import org.springframework.web.util.ContentCachingRequestWrapper;
+
+import javax.servlet.*;
+import javax.servlet.annotation.WebFilter;
+import javax.servlet.http.HttpServletRequest;
+import java.io.IOException;
+
+@WebFilter(urlPatterns = "/*")
+public class CacheRequestContentFilter implements Filter {
+
+    @Override
+    public void doFilter(ServletRequest request, ServletResponse response, FilterChain chain) throws ServletException, IOException {
+        if (request instanceof HttpServletRequest) {
+            String contentType = request.getContentType();
+            if (contentType == null || !contentType.contains("multipart/form-data")) {
+                request = new ContentCachingRequestWrapper((HttpServletRequest) request);
+            }
+        }
+        chain.doFilter(request, response);
+    }
+}
@@ -0,0 +1,47 @@
+package com.baeldung.filters;
+
+import org.junit.jupiter.api.Test;
+import org.springframework.mock.web.MockFilterChain;
+import org.springframework.mock.web.MockHttpServletRequest;
+import org.springframework.mock.web.MockHttpServletResponse;
+import org.springframework.web.util.ContentCachingRequestWrapper;
+
+import javax.servlet.Filter;
+import javax.servlet.ServletException;
+import javax.servlet.ServletInputStream;
+import javax.servlet.ServletRequest;
+import javax.servlet.http.HttpServletRequest;
+import java.io.IOException;
+
+import static org.junit.jupiter.api.Assertions.*;
+
+public class HttpRequestUnitTest {
+
+    @Test
+    public void givenHttpServletRequest_whenCalling_getReaderAfter_getInputStream_thenThrowIllegalStateException() throws IOException {
+        HttpServletRequest request = new MockHttpServletRequest();
+        try (ServletInputStream ignored = request.getInputStream()) {
+            IllegalStateException exception = assertThrows(IllegalStateException.class, request::getReader);
+            assertEquals("Cannot call getReader() after getInputStream() has already been called for the current request",
+                    exception.getMessage());
+        }
+    }
+
+    @Test
+    public void givenServletRequest_whenDoFilter_thenCanCallBoth() throws ServletException, IOException {
+        MockHttpServletRequest req = new MockHttpServletRequest();
+        MockHttpServletResponse res = new MockHttpServletResponse();
+        MockFilterChain chain = new MockFilterChain();
+
+        Filter filter = new CacheRequestContentFilter();
+        filter.doFilter(req, res, chain);
+
+        ServletRequest request = chain.getRequest();
+        assertTrue(request instanceof ContentCachingRequestWrapper);
+
+        // now we can call both getInputStream() and getReader()
+        request.getInputStream();
+        request.getReader();
+    }
+
+}