Merge pull request #7398 from rahulgul8/development

Checking if a URL Exists in Java

core-java-modules/core-java-networking-2/.gitignore

@@ -0,0 +1,25 @@
+*.class
+
+0.*
+
+#folders#
+/target
+/neoDb*
+/data
+/src/main/webapp/WEB-INF/classes
+*/META-INF/*
+.resourceCache
+
+# Packaged files #
+*.jar
+*.war
+*.ear
+
+# Files generated by integration tests
+backup-pom.xml
+/bin/
+/temp
+
+#IntelliJ specific
+.idea/
+*.iml

core-java-modules/core-java-networking-2/pom.xml

@@ -0,0 +1,20 @@
+<project xmlns="http://maven.apache.org/POM/4.0.0" xmlns:xsi="http://www.w3.org/2001/XMLSchema-instance"
+         xsi:schemaLocation="http://maven.apache.org/POM/4.0.0 http://maven.apache.org/xsd/maven-4.0.0.xsd">
+    <modelVersion>4.0.0</modelVersion>
+    <artifactId>core-java-networking-2</artifactId>
+    <name>core-java-networking-2</name>
+    <packaging>jar</packaging>
+
+    <parent>
+        <groupId>com.baeldung.core-java-modules</groupId>
+        <artifactId>core-java-modules</artifactId>
+        <version>1.0.0-SNAPSHOT</version>
+    </parent>
+
+    <dependencies>
+    </dependencies>
+
+    <build>
+        <finalName>core-java-networking-2</finalName>
+    </build>	
+</project>

core-java-modules/core-java-networking-2/src/main/java/com/baeldung/url/UrlChecker.java

@@ -0,0 +1,25 @@
+package com.baeldung.url;
+
+import java.io.IOException;
+import java.net.HttpURLConnection;
+import java.net.URL;
+
+public class UrlChecker {
+
+    public int getResponseCodeForURL(String address) throws IOException {
+        return getResponseCodeForURLUsing(address, "GET");
+    }
+
+    public int getResponseCodeForURLUsingHead(String address) throws IOException {
+        return getResponseCodeForURLUsing(address, "HEAD");
+    }
+
+    private int getResponseCodeForURLUsing(String address, String method) throws IOException {
+        HttpURLConnection.setFollowRedirects(false); // Set follow redirects to false
+        final URL url = new URL(address);
+        HttpURLConnection huc = (HttpURLConnection) url.openConnection();
+        huc.setRequestMethod(method);
+        return huc.getResponseCode();
+    }
+
+}

core-java-modules/core-java-networking-2/src/test/java/com/baeldung/url/UrlCheckerUnitTest.java

@@ -0,0 +1,39 @@
+package com.baeldung.url;
+
+import static org.junit.jupiter.api.Assertions.assertEquals;
+
+import java.io.IOException;
+
+import org.junit.Test;
+
+public class UrlCheckerUnitTest {
+
+    @Test
+    public void givenValidUrl_WhenUsingHEAD_ThenReturn200() throws IOException {
+        UrlChecker tester = new UrlChecker();
+        int responseCode = tester.getResponseCodeForURLUsingHead("http://www.example.com");
+        assertEquals(200, responseCode);
+    }
+    
+    @Test
+    public void givenInvalidIUrl_WhenUsingHEAD_ThenReturn404() throws IOException {
+        UrlChecker tester = new UrlChecker();
+        int responseCode = tester.getResponseCodeForURLUsingHead("http://www.example.com/unkownurl");
+        assertEquals(404, responseCode);
+    }
+    
+    @Test
+    public void givenValidUrl_WhenUsingGET_ThenReturn200() throws IOException {
+        UrlChecker tester = new UrlChecker();
+        int responseCode = tester.getResponseCodeForURL("http://www.example.com");
+        assertEquals(200, responseCode);
+    }
+    
+    @Test
+    public void givenInvalidIUrl_WhenUsingGET_ThenReturn404() throws IOException {
+        UrlChecker tester = new UrlChecker();
+        int responseCode = tester.getResponseCodeForURL("http://www.example.com/unkownurl");
+        assertEquals(404, responseCode);
+    }
+    
+}

core-java-modules/pom.xml

@@ -17,6 +17,7 @@
         <module>pre-jpms</module>
         <module>core-java-exceptions</module>
         <module>core-java-optional</module>
+        <module>core-java-networking-2</module>
     </modules>
     
 </project>