How to add a filter in Spring Boot

Spring-Boot/spring-boot-example/src/main/java/com/javadevjournal/commandline/CustomCommandLineRunner.java

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+package com.javadevjournal.commandline;
+
+import org.slf4j.Logger;
+import org.slf4j.LoggerFactory;
+import org.springframework.boot.CommandLineRunner;
+import org.springframework.core.Ordered;
+import org.springframework.stereotype.Component;
+
+import java.util.Arrays;
+
+@Component
+public class CustomCommandLineRunner implements CommandLineRunner,Ordered {
+
+    private static final Logger LOG= LoggerFactory.getLogger(CustomCommandLineRunner.class);
+
+    @Override
+    public void run(String... args) throws Exception {
+        LOG.info("Custom command line runner is excuted with command line arguments: {}" , Arrays.toString(args));
+    }
+
+    @Override
+    public int getOrder() {
+        return 2;
+    }
+}

Spring-Boot/spring-boot-example/src/main/java/com/javadevjournal/commandline/CustomCommandLineRunner2.java

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+package com.javadevjournal.commandline;
+
+import org.slf4j.Logger;
+import org.slf4j.LoggerFactory;
+import org.springframework.boot.CommandLineRunner;
+import org.springframework.core.annotation.Order;
+import org.springframework.stereotype.Component;
+
+import java.util.Arrays;
+
+@Component
+@Order(1)
+public class CustomCommandLineRunner2 implements CommandLineRunner {
+
+    private static final Logger LOG= LoggerFactory.getLogger(CustomCommandLineRunner2.class);
+
+    @Override
+    public void run(String... args) throws Exception {
+       LOG.info("Calling second command line runner with arguments {}" , Arrays.toString(args));
+    }
+}

Spring-Boot/spring-boot-example/src/main/java/com/javadevjournal/deferredresult/BlockingRESTController.java

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+package com.javadevjournal.deferredresult;
+
+import org.springframework.http.ResponseEntity;
+import org.springframework.web.bind.annotation.GetMapping;
+import org.springframework.web.bind.annotation.RestController;
+
+@RestController
+public class BlockingRESTController {
+
+    @GetMapping("/blocking-request")
+    public ResponseEntity<?> blockHttpRequest() throws InterruptedException {
+
+        Thread.sleep(40000);
+        return  ResponseEntity.ok("OK");
+    }
+}

Spring-Boot/spring-boot-example/src/main/java/com/javadevjournal/deferredresult/DeferredResultController.java

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+package com.javadevjournal.deferredresult;
+
+import org.slf4j.Logger;
+import org.slf4j.LoggerFactory;
+import org.springframework.http.HttpStatus;
+import org.springframework.http.ResponseEntity;
+import org.springframework.ui.Model;
+import org.springframework.web.bind.annotation.GetMapping;
+import org.springframework.web.bind.annotation.RestController;
+import org.springframework.web.context.request.async.DeferredResult;
+
+import java.util.concurrent.ForkJoinPool;
+
+@RestController
+public class DeferredResultController {
+
+    private static final Logger LOGGER = LoggerFactory.getLogger(DeferredResultController.class);
+
+    @GetMapping("/asynchronous-request")
+    public DeferredResult<ResponseEntity<?>> asynchronousRequestProcessing(final Model model){
+
+        LOGGER.info("Started processing asynchronous request");
+        final DeferredResult<ResponseEntity<?>> deferredResult = new DeferredResult<>();
+
+        /**
+         * Section to simulate slow running thread blocking process
+         */
+        ForkJoinPool forkJoinPool = new ForkJoinPool();
+        forkJoinPool.submit(() -> {
+            LOGGER.info("Processing request in new thread");
+                try {
+                    Thread.sleep(4000);
+
+                } catch (InterruptedException e) {
+                    LOGGER.error("InterruptedException while executing the thread {}" , e.fillInStackTrace());
+                }
+                deferredResult.setResult(ResponseEntity.ok("OK"));
+            });
+
+        LOGGER.info("HTTP Wroker thread is relased.");
+        deferredResult.onCompletion(() -> LOGGER.info("Processing complete"));
+        return deferredResult;
+    }
+
+    @GetMapping("/timeout-request")
+    public DeferredResult<ResponseEntity<?>> onTimeoutExample(final Model model){
+
+        LOGGER.info("Started processing asynchronous request");
+        final DeferredResult<ResponseEntity<?>> deferredResult = new DeferredResult<ResponseEntity<?>>(5000l);
+        deferredResult.onTimeout(() ->
+                deferredResult.setErrorResult(
+                        ResponseEntity.status(HttpStatus.REQUEST_TIMEOUT)
+                                .body("Request timeout.")));
+        /**
+         * Section to simulate slow running thread blocking process
+         */
+        ForkJoinPool forkJoinPool = new ForkJoinPool();
+        forkJoinPool.submit(() -> {
+            LOGGER.info("Processing request in new thread");
+            try {
+                Thread.sleep(6000);
+
+            } catch (InterruptedException e) {
+                LOGGER.error("InterruptedException while executing the thread {}" , e.fillInStackTrace());
+            }
+            deferredResult.setResult(ResponseEntity.ok("OK"));
+        });
+
+        LOGGER.info("HTTP Wroker thread is relased.");
+        return deferredResult;
+    }
+
+
+}