[JENKINS-66326] Prepare SCM Sync Configuration for core Guava upgrade

pom.xml

@@ -46,14 +46,14 @@
   <repositories>
     <repository>
         <id>repo.jenkins-ci.org</id>
-        <url>http://repo.jenkins-ci.org/public/</url>
+        <url>https://repo.jenkins-ci.org/public/</url>
     </repository>
   </repositories>
 
   <pluginRepositories>
     <pluginRepository>
         <id>repo.jenkins-ci.org</id>
-        <url>http://repo.jenkins-ci.org/public/</url>
+        <url>https://repo.jenkins-ci.org/public/</url>
     </pluginRepository>
   </pluginRepositories>
 

src/main/java/hudson/plugins/scm_sync_configuration/utils/Checksums.java

@@ -1,26 +1,44 @@
 package hudson.plugins.scm_sync_configuration.utils;
 
-import com.google.common.io.ByteStreams;
-import com.google.common.io.Files;
-
 import java.io.File;
+import java.io.FileInputStream;
 import java.io.IOException;
 import java.util.zip.CRC32;
+import java.util.zip.CheckedInputStream;
 import java.util.zip.Checksum;
 
 /**
  * @author fcamblor
  * Utility class allowing to provide easy access to jenkins files checksums
  */
 public class Checksums {
+
+    private static final int BUF_SIZE = 0x1000; // 4K
+
     public static boolean fileAndByteArrayContentAreEqual(File file, byte[] content) throws IOException {
         if(!file.exists()){
             return content == null || content.length == 0;
         }
 
+        long fileChecksum;
+        CheckedInputStream in = null;
+        try {
+            in = new CheckedInputStream(new FileInputStream(file), createChecksum());
+            byte[] buffer = new byte[BUF_SIZE];
+            while (in.read(buffer, 0, buffer.length) >= 0) {
+                // keep updating checksum
+            }
+            fileChecksum = in.getChecksum().getValue();
+        } finally {
+            if (in != null) {
+                in.close();
+            }
+        }
+
         Checksum checksum = createChecksum();
-        long fileChecksum = Files.getChecksum(file, checksum);
-        long contentChecksum = ByteStreams.getChecksum(ByteStreams.newInputStreamSupplier(content), checksum);
+        checksum.update(content, 0, content.length);
+        long contentChecksum = checksum.getValue();
+
         return fileChecksum == contentChecksum;
     }