Merge branch '1.5.x'

spring-boot-project/spring-boot/src/main/java/org/springframework/boot/web/servlet/support/ErrorPageFilter.java

@@ -17,6 +17,7 @@
 package org.springframework.boot.web.servlet.support;
 
 import java.io.IOException;
+import java.io.PrintWriter;
 import java.util.HashMap;
 import java.util.Map;
 
@@ -24,6 +25,7 @@ import javax.servlet.Filter;
 import javax.servlet.FilterChain;
 import javax.servlet.FilterConfig;
 import javax.servlet.ServletException;
+import javax.servlet.ServletOutputStream;
 import javax.servlet.ServletRequest;
 import javax.servlet.ServletResponse;
 import javax.servlet.http.HttpServletRequest;
@@ -311,11 +313,15 @@ public class ErrorPageFilter implements Filter, ErrorPageRegistry {
 
 		@Override
 		public void flushBuffer() throws IOException {
+			sendErrorIfNecessary();
+			super.flushBuffer();
+		}
+
+		private void sendErrorIfNecessary() throws IOException {
 			if (this.hasErrorToSend && !isCommitted()) {
 				((HttpServletResponse) getResponse()).sendError(this.status,
 						this.message);
 			}
-			super.flushBuffer();
 		}
 
 		public String getMessage() {
@@ -326,6 +332,19 @@ public class ErrorPageFilter implements Filter, ErrorPageRegistry {
 			return this.hasErrorToSend;
 		}
 
+		@Override
+		public PrintWriter getWriter() throws IOException {
+			sendErrorIfNecessary();
+			return super.getWriter();
+
+		}
+
+		@Override
+		public ServletOutputStream getOutputStream() throws IOException {
+			sendErrorIfNecessary();
+			return super.getOutputStream();
+		}
+
 	}
 
 }

spring-boot-project/spring-boot/src/test/java/org/springframework/boot/web/servlet/support/ErrorPageFilterTests.java

@@ -521,6 +521,22 @@ public class ErrorPageFilterTests {
 		assertThat(this.response.getForwardedUrl()).isEqualTo("/500");
 	}
 
+	@Test
+	public void whenErrorIsSentAndWriterIsFlushedErrorIsSentToTheClient()
+			throws Exception {
+		this.chain = new MockFilterChain() {
+			@Override
+			public void doFilter(ServletRequest request, ServletResponse response)
+					throws IOException, ServletException {
+				((HttpServletResponse) response).sendError(400);
+				response.getWriter().flush();
+				super.doFilter(request, response);
+			}
+		};
+		this.filter.doFilter(this.request, this.response, this.chain);
+		assertThat(this.response.getStatus()).isEqualTo(400);
+	}
+
 	private void setUpAsyncDispatch() throws Exception {
 		this.request.setAsyncSupported(true);
 		this.request.setAsyncStarted(true);