HADOOP-14184. Remove service loader config entry for ftp fs. Contributed by Sen Zhao.

hadoop-common-project/hadoop-common/src/main/resources/META-INF/services/org.apache.hadoop.fs.FileSystem

@@ -15,7 +15,6 @@
 
 org.apache.hadoop.fs.LocalFileSystem
 org.apache.hadoop.fs.viewfs.ViewFileSystem
-org.apache.hadoop.fs.ftp.FTPFileSystem
 org.apache.hadoop.fs.HarFileSystem
 org.apache.hadoop.fs.http.HttpFileSystem
 org.apache.hadoop.fs.http.HttpsFileSystem

hadoop-common-project/hadoop-common/src/main/resources/core-default.xml

@@ -815,6 +815,12 @@
   <description>The FileSystem for Ftp: uris.</description>
 </property>
 
+<property>
+  <name>fs.ftp.impl</name>
+  <value>org.apache.hadoop.fs.ftp.FTPFileSystem</value>
+  <description>The implementation class of the FTP FileSystem</description>
+</property>
+
 <property>
   <name>fs.AbstractFileSystem.webhdfs.impl</name>
   <value>org.apache.hadoop.fs.WebHdfs</value>

hadoop-common-project/hadoop-common/src/test/java/org/apache/hadoop/conf/TestCommonConfigurationFields.java

@@ -99,6 +99,10 @@ public class TestCommonConfigurationFields extends TestConfigurationFieldsBase {
     // S3A properties are in a different subtree.
     xmlPrefixToSkipCompare.add("fs.s3a.");
 
+    //ftp properties are in a different subtree.
+    // - org.apache.hadoop.fs.ftp.FTPFileSystem.
+    xmlPrefixToSkipCompare.add("fs.ftp.impl");
+
     // WASB properties are in a different subtree.
     // - org.apache.hadoop.fs.azure.NativeAzureFileSystem
     xmlPrefixToSkipCompare.add("fs.wasb.impl");