RANGER-5046: checkstyle compliance updates - plugin-ozone (#429)

Co-authored-by: Madhan Neethiraj <mneethiraj@users.noreply.github.com>
diff --git a/plugin-ozone/pom.xml b/plugin-ozone/pom.xml
index 1849835..30b92d1 100644
--- a/plugin-ozone/pom.xml
+++ b/plugin-ozone/pom.xml
@@ -28,6 +28,8 @@
     <name>Ozone Security Plugin</name>
     <description>Ozone Security Plugin</description>
     <properties>
+        <checkstyle.failOnViolation>true</checkstyle.failOnViolation>
+        <checkstyle.skip>false</checkstyle.skip>
         <project.build.sourceEncoding>UTF-8</project.build.sourceEncoding>
     </properties>
     <dependencies>
diff --git a/plugin-ozone/src/main/java/org/apache/ranger/authorization/ozone/authorizer/RangerOzoneAuthorizer.java b/plugin-ozone/src/main/java/org/apache/ranger/authorization/ozone/authorizer/RangerOzoneAuthorizer.java
index 3bd17d5..a079b08 100644
--- a/plugin-ozone/src/main/java/org/apache/ranger/authorization/ozone/authorizer/RangerOzoneAuthorizer.java
+++ b/plugin-ozone/src/main/java/org/apache/ranger/authorization/ozone/authorizer/RangerOzoneAuthorizer.java
@@ -39,178 +39,186 @@
 import java.util.Date;
 
 public class RangerOzoneAuthorizer implements IAccessAuthorizer {
-	public static final String ACCESS_TYPE_READ = "read";
-	public static final String ACCESS_TYPE_WRITE = "write";
-	public static final String ACCESS_TYPE_CREATE = "create";
-	public static final String ACCESS_TYPE_LIST = "list";
-	public static final String ACCESS_TYPE_DELETE = "delete";
-	public static final String ACCESS_TYPE_READ_ACL = "read_acl";
-	public static final String ACCESS_TYPE_WRITE_ACL = "write_acl";
+    private static final Logger LOG                        = LoggerFactory.getLogger(RangerOzoneAuthorizer.class);
+    private static final Logger PERF_OZONEAUTH_REQUEST_LOG = RangerPerfTracer.getPerfLogger("ozoneauth.request");
 
+    public static final String ACCESS_TYPE_READ      = "read";
+    public static final String ACCESS_TYPE_WRITE     = "write";
+    public static final String ACCESS_TYPE_CREATE    = "create";
+    public static final String ACCESS_TYPE_LIST      = "list";
+    public static final String ACCESS_TYPE_DELETE    = "delete";
+    public static final String ACCESS_TYPE_READ_ACL  = "read_acl";
+    public static final String ACCESS_TYPE_WRITE_ACL = "write_acl";
+    public static final String KEY_RESOURCE_VOLUME   = "volume";
+    public static final String KEY_RESOURCE_BUCKET   = "bucket";
+    public static final String KEY_RESOURCE_KEY      = "key";
 
-    public static final String KEY_RESOURCE_VOLUME = "volume";
-	public static final String KEY_RESOURCE_BUCKET = "bucket";
-	public static final String KEY_RESOURCE_KEY = "key";
+    private static volatile RangerBasePlugin rangerPlugin;
 
-	private static final Logger PERF_OZONEAUTH_REQUEST_LOG = RangerPerfTracer.getPerfLogger("ozoneauth.request");
+    RangerDefaultAuditHandler auditHandler;
 
-    private static final Logger LOG = LoggerFactory.getLogger(RangerOzoneAuthorizer.class);
+    public RangerOzoneAuthorizer() {
+        RangerBasePlugin plugin = rangerPlugin;
 
-	private static volatile RangerBasePlugin rangerPlugin = null;
-	RangerDefaultAuditHandler auditHandler = null;
+        if (plugin == null) {
+            synchronized (RangerOzoneAuthorizer.class) {
+                plugin = rangerPlugin;
 
-	public RangerOzoneAuthorizer() {
-		RangerBasePlugin plugin = rangerPlugin;
+                if (plugin == null) {
+                    plugin = new RangerBasePlugin("ozone", "ozone");
 
-		if (plugin == null) {
-			synchronized (RangerOzoneAuthorizer.class) {
-				plugin = rangerPlugin;
+                    plugin.init(); // this will initialize policy engine and policy refresher
 
-				if (plugin == null) {
-					plugin = new RangerBasePlugin("ozone", "ozone");
-					plugin.init(); // this will initialize policy engine and policy refresher
+                    auditHandler = new RangerDefaultAuditHandler();
 
-					auditHandler = new RangerDefaultAuditHandler();
-					plugin.setResultProcessor(auditHandler);
+                    plugin.setResultProcessor(auditHandler);
 
-					rangerPlugin = plugin;
-				}
-			}
-		}
-	}
+                    rangerPlugin = plugin;
+                }
+            }
+        }
+    }
 
-	@Override
-	public boolean checkAccess(IOzoneObj ozoneObject, RequestContext context) {
-		boolean returnValue = false;
-		if (ozoneObject == null) {
-			LOG.error("Ozone object is null!!");
-			return returnValue;
-		}
-		OzoneObj ozoneObj = (OzoneObj) ozoneObject;
-		UserGroupInformation ugi = context.getClientUgi();
-		ACLType operation = context.getAclRights();
-		String resource = ozoneObj.getPath();
+    @Override
+    public boolean checkAccess(IOzoneObj ozoneObject, RequestContext context) {
+        boolean returnValue = false;
 
-		if (LOG.isDebugEnabled()) {
-			LOG.debug("==> RangerOzoneAuthorizer.checkAccess with operation = " + operation + ", resource = " +
-					resource + ", store type = " + OzoneObj.StoreType.values() + ", ugi = " + ugi + ", ip = " +
-					context.getIp() + ", resourceType = " + ozoneObj.getResourceType() + ")");
-		}
+        if (ozoneObject == null) {
+            LOG.error("Ozone object is null!!");
 
-		if (rangerPlugin == null) {
-			MiscUtil.logErrorMessageByInterval(LOG,
-					"Authorizer is still not initialized");
-			return returnValue;
-		}
+            return false;
+        }
 
-		//TODO: If sorce type is S3 and resource is volume, then allow it by default
-		if (ozoneObj.getStoreType() == OzoneObj.StoreType.S3 && ozoneObj.getResourceType() == OzoneObj.ResourceType.VOLUME) {
-			if (LOG.isDebugEnabled()) {
-				LOG.debug("If store type is s3 and resource is volume, then we allow it by default!  Returning true");
-			}
-			LOG.warn("Allowing access by default since source type is S3 and resource type is Volume!!");
-			return true;
-		}
+        OzoneObj             ozoneObj  = (OzoneObj) ozoneObject;
+        UserGroupInformation ugi       = context.getClientUgi();
+        ACLType              operation = context.getAclRights();
+        String               resource  = ozoneObj.getPath();
 
-		RangerPerfTracer perf = null;
+        LOG.debug("==> RangerOzoneAuthorizer.checkAccess with operation = {}, resource = {}, store type = {}, ugi = {}, ip = {}, resourceType = {}", operation, resource, OzoneObj.StoreType.values(), ugi, context.getIp(), ozoneObj.getResourceType());
 
-		if (RangerPerfTracer.isPerfTraceEnabled(PERF_OZONEAUTH_REQUEST_LOG)) {
-			perf = RangerPerfTracer.getPerfTracer(PERF_OZONEAUTH_REQUEST_LOG, "RangerOzoneAuthorizer.authorize(resource=" + resource + ")");
-		}
+        if (rangerPlugin == null) {
+            MiscUtil.logErrorMessageByInterval(LOG, "Authorizer is still not initialized");
 
-		Date eventTime = new Date();
-		String accessType = mapToRangerAccessType(operation);
-		if (accessType == null) {
-			MiscUtil.logErrorMessageByInterval(LOG,
-					"Unsupported access type. operation=" + operation) ;
-			LOG.error("Unsupported access type. operation=" + operation + ", resource=" + resource);
-			return returnValue;
-		}
-		String action = accessType;
-		String clusterName = rangerPlugin.getClusterName();
+            return false;
+        }
 
-		RangerAccessRequestImpl rangerRequest = new RangerAccessRequestImpl();
-		rangerRequest.setUser(ugi.getShortUserName());
-		rangerRequest.setUserGroups(Sets.newHashSet(ugi.getGroupNames()));
-		rangerRequest.setClientIPAddress(context.getIp().getHostAddress());
-		rangerRequest.setRemoteIPAddress(context.getIp().getHostAddress());
-		rangerRequest.setAccessTime(eventTime);
+        //TODO: If source type is S3 and resource is volume, then allow it by default
+        if (ozoneObj.getStoreType() == OzoneObj.StoreType.S3 && ozoneObj.getResourceType() == OzoneObj.ResourceType.VOLUME) {
+            LOG.debug("If store type is s3 and resource is volume, then we allow it by default!  Returning true");
+            LOG.warn("Allowing access by default since source type is S3 and resource type is Volume!!");
 
-		RangerAccessResourceImpl rangerResource = new RangerAccessResourceImpl();
-		rangerResource.setOwnerUser(context.getOwnerName());
+            return true;
+        }
 
-		rangerRequest.setResource(rangerResource);
-		rangerRequest.setAccessType(accessType);
-		rangerRequest.setAction(action);
-		rangerRequest.setRequestData(resource);
-		rangerRequest.setClusterName(clusterName);
+        RangerPerfTracer perf = null;
 
-		if (ozoneObj.getResourceType() == OzoneObj.ResourceType.VOLUME) {
-			rangerResource.setValue(KEY_RESOURCE_VOLUME, ozoneObj.getVolumeName());
-		} else if (ozoneObj.getResourceType() == OzoneObj.ResourceType.BUCKET || ozoneObj.getResourceType() == OzoneObj.ResourceType.KEY) {
-			if (ozoneObj.getStoreType() == OzoneObj.StoreType.S3) {
-				rangerResource.setValue(KEY_RESOURCE_VOLUME, "s3Vol");
-			} else {
-				rangerResource.setValue(KEY_RESOURCE_VOLUME, ozoneObj.getVolumeName());
-			}
-			rangerResource.setValue(KEY_RESOURCE_BUCKET, ozoneObj.getBucketName());
-			if (ozoneObj.getResourceType() == OzoneObj.ResourceType.KEY) {
-				rangerResource.setValue(KEY_RESOURCE_KEY, ozoneObj.getKeyName());
-			}
-		} else {
-			LOG.error("Unsupported resource = " + resource);
-			MiscUtil.logErrorMessageByInterval(LOG, "Unsupported resource type " + ozoneObj.getResourceType() + " for resource = " + resource
-					+ ", request=" + rangerRequest);
-			return returnValue;
-		}
+        if (RangerPerfTracer.isPerfTraceEnabled(PERF_OZONEAUTH_REQUEST_LOG)) {
+            perf = RangerPerfTracer.getPerfTracer(PERF_OZONEAUTH_REQUEST_LOG, String.format("RangerOzoneAuthorizer.authorize(resource = %s)", resource));
+        }
 
-		try {
-			RangerAccessResult result = rangerPlugin
-					.isAccessAllowed(rangerRequest);
-			if (result == null) {
-				LOG.error("Ranger Plugin returned null. Returning false");
-			} else {
-				returnValue = result.getIsAllowed();
-			}
-		} catch (Throwable t) {
-			LOG.error("Error while calling isAccessAllowed(). request="
-					+ rangerRequest, t);
-		}
-		RangerPerfTracer.log(perf);
+        Date   eventTime  = new Date();
+        String accessType = mapToRangerAccessType(operation);
 
-		if (LOG.isDebugEnabled()) {
-			LOG.debug("rangerRequest=" + rangerRequest + ", return="
-					+ returnValue);
-		}
-		return returnValue;
-	}
+        if (accessType == null) {
+            String message = String.format("Unsupported access type. operation = %s", operation);
 
-	private String mapToRangerAccessType(ACLType operation) {
-		String rangerAccessType = null;
-		switch (operation) {
-			case READ:
-				rangerAccessType = ACCESS_TYPE_READ;
-				break;
-			case WRITE:
-				rangerAccessType = ACCESS_TYPE_WRITE;
-				break;
-			case CREATE:
-				rangerAccessType = ACCESS_TYPE_CREATE;
-				break;
-			case DELETE:
-				rangerAccessType = ACCESS_TYPE_DELETE;
-				break;
-			case LIST:
-				rangerAccessType = ACCESS_TYPE_LIST;
-				break;
-			case READ_ACL:
-				rangerAccessType = ACCESS_TYPE_READ_ACL;
-				break;
-			case WRITE_ACL:
-				rangerAccessType = ACCESS_TYPE_WRITE_ACL;
-				break;
-		}
-		return rangerAccessType;
-	}
+            MiscUtil.logErrorMessageByInterval(LOG, message);
+            LOG.error("{}, resource = {}", message, resource);
+
+            return false;
+        }
+
+        String                  clusterName   = rangerPlugin.getClusterName();
+        RangerAccessRequestImpl rangerRequest = new RangerAccessRequestImpl();
+
+        rangerRequest.setUser(ugi.getShortUserName());
+        rangerRequest.setUserGroups(Sets.newHashSet(ugi.getGroupNames()));
+        rangerRequest.setClientIPAddress(context.getIp().getHostAddress());
+        rangerRequest.setRemoteIPAddress(context.getIp().getHostAddress());
+        rangerRequest.setAccessTime(eventTime);
+
+        RangerAccessResourceImpl rangerResource = new RangerAccessResourceImpl();
+
+        rangerResource.setOwnerUser(context.getOwnerName());
+        rangerRequest.setResource(rangerResource);
+        rangerRequest.setAccessType(accessType);
+        rangerRequest.setAction(accessType);
+        rangerRequest.setRequestData(resource);
+        rangerRequest.setClusterName(clusterName);
+
+        if (ozoneObj.getResourceType() == OzoneObj.ResourceType.VOLUME) {
+            rangerResource.setValue(KEY_RESOURCE_VOLUME, ozoneObj.getVolumeName());
+        } else if (ozoneObj.getResourceType() == OzoneObj.ResourceType.BUCKET || ozoneObj.getResourceType() == OzoneObj.ResourceType.KEY) {
+            if (ozoneObj.getStoreType() == OzoneObj.StoreType.S3) {
+                rangerResource.setValue(KEY_RESOURCE_VOLUME, "s3Vol");
+            } else {
+                rangerResource.setValue(KEY_RESOURCE_VOLUME, ozoneObj.getVolumeName());
+            }
+
+            rangerResource.setValue(KEY_RESOURCE_BUCKET, ozoneObj.getBucketName());
+
+            if (ozoneObj.getResourceType() == OzoneObj.ResourceType.KEY) {
+                rangerResource.setValue(KEY_RESOURCE_KEY, ozoneObj.getKeyName());
+            }
+        } else {
+            LOG.error("Unsupported resource = {}", resource);
+
+            String message = String.format("Unsupported resource type = %s for resource = %s, request = %s", ozoneObj.getResourceType(), resource, rangerRequest);
+            MiscUtil.logErrorMessageByInterval(LOG, message);
+
+            return false;
+        }
+
+        try {
+            RangerAccessResult result = rangerPlugin.isAccessAllowed(rangerRequest);
+
+            if (result == null) {
+                LOG.error("Ranger Plugin returned null. Returning false");
+            } else {
+                returnValue = result.getIsAllowed();
+            }
+        } catch (Throwable t) {
+            LOG.error("Error while calling isAccessAllowed(). request = {}", rangerRequest, t);
+        }
+
+        RangerPerfTracer.log(perf);
+
+        LOG.debug("rangerRequest = {}, return = {}", rangerRequest, returnValue);
+
+        return returnValue;
+    }
+
+    private String mapToRangerAccessType(ACLType operation) {
+        final String rangerAccessType;
+
+        switch (operation) {
+            case READ:
+                rangerAccessType = ACCESS_TYPE_READ;
+                break;
+            case WRITE:
+                rangerAccessType = ACCESS_TYPE_WRITE;
+                break;
+            case CREATE:
+                rangerAccessType = ACCESS_TYPE_CREATE;
+                break;
+            case DELETE:
+                rangerAccessType = ACCESS_TYPE_DELETE;
+                break;
+            case LIST:
+                rangerAccessType = ACCESS_TYPE_LIST;
+                break;
+            case READ_ACL:
+                rangerAccessType = ACCESS_TYPE_READ_ACL;
+                break;
+            case WRITE_ACL:
+                rangerAccessType = ACCESS_TYPE_WRITE_ACL;
+                break;
+            default:
+                LOG.error("Unknown operation!");
+                rangerAccessType = null;
+                break;
+        }
+
+        return rangerAccessType;
+    }
 }
-
diff --git a/plugin-ozone/src/main/java/org/apache/ranger/services/ozone/RangerServiceOzone.java b/plugin-ozone/src/main/java/org/apache/ranger/services/ozone/RangerServiceOzone.java
index 08dc56e..19d7b7e 100644
--- a/plugin-ozone/src/main/java/org/apache/ranger/services/ozone/RangerServiceOzone.java
+++ b/plugin-ozone/src/main/java/org/apache/ranger/services/ozone/RangerServiceOzone.java
@@ -22,10 +22,10 @@
 import org.apache.commons.lang.StringUtils;
 import org.apache.ranger.plugin.client.HadoopException;
 import org.apache.ranger.plugin.model.RangerPolicy;
-import org.apache.ranger.plugin.model.RangerService;
-import org.apache.ranger.plugin.model.RangerServiceDef;
 import org.apache.ranger.plugin.model.RangerPolicy.RangerPolicyItem;
 import org.apache.ranger.plugin.model.RangerPolicy.RangerPolicyItemAccess;
+import org.apache.ranger.plugin.model.RangerService;
+import org.apache.ranger.plugin.model.RangerServiceDef;
 import org.apache.ranger.plugin.policyengine.RangerPolicyEngine;
 import org.apache.ranger.plugin.service.RangerBaseService;
 import org.apache.ranger.plugin.service.ResourceLookupContext;
@@ -40,17 +40,16 @@
 import java.util.Map;
 
 public class RangerServiceOzone extends RangerBaseService {
-
     private static final Logger LOG = LoggerFactory.getLogger(RangerServiceOzone.class);
-    public static final String ACCESS_TYPE_READ  = "read";
-    public static final String ACCESS_TYPE_WRITE  = "write";
-    public static final String ACCESS_TYPE_CREATE  = "create";
-    public static final String ACCESS_TYPE_LIST  = "list";
-    public static final String ACCESS_TYPE_DELETE  = "delete";
-    public static final String ACCESS_TYPE_READ_ACL = "read_acl";
-    public static final String ACCESS_TYPE_WRITE_ACL = "write_acl";
-    public static final String ACCESS_TYPE_ALL  = "all";
 
+    public static final String ACCESS_TYPE_READ      = "read";
+    public static final String ACCESS_TYPE_WRITE     = "write";
+    public static final String ACCESS_TYPE_CREATE    = "create";
+    public static final String ACCESS_TYPE_LIST      = "list";
+    public static final String ACCESS_TYPE_DELETE    = "delete";
+    public static final String ACCESS_TYPE_READ_ACL  = "read_acl";
+    public static final String ACCESS_TYPE_WRITE_ACL = "write_acl";
+    public static final String ACCESS_TYPE_ALL       = "all";
 
     public RangerServiceOzone() {
         super();
@@ -62,90 +61,89 @@ public void init(RangerServiceDef serviceDef, RangerService service) {
     }
 
     @Override
-    public Map<String,Object> validateConfig() throws Exception {
-        Map<String, Object> ret = new HashMap<String, Object>();
-        String serviceName = getServiceName();
-        if(LOG.isDebugEnabled()) {
-            LOG.debug("<== RangerServiceOzone.validateConfig Service: (" + serviceName + " )");
-        }
+    public Map<String, Object> validateConfig() throws Exception {
+        Map<String, Object> ret         = new HashMap<>();
+        String              serviceName = getServiceName();
 
-        if ( configs != null) {
-            try  {
+        LOG.debug("<== RangerServiceOzone.validateConfig Service: ({})", serviceName);
+
+        if (configs != null) {
+            try {
                 ret = OzoneResourceMgr.connectionTest(serviceName, configs);
             } catch (HadoopException e) {
-                LOG.error("<== RangerServiceOzone.validateConfig Error: " + e.getMessage(),e);
+                LOG.error("<== RangerServiceOzone.validateConfig Error: {}", e.getMessage(), e);
                 throw e;
             }
         }
 
-        if(LOG.isDebugEnabled()) {
-            LOG.debug("<== RangerServiceOzone.validateConfig Response : (" + ret + " )");
-        }
+        LOG.debug("<== RangerServiceOzone.validateConfig Response : ({})", ret);
 
         return ret;
     }
 
     @Override
     public List<String> lookupResource(ResourceLookupContext context) throws Exception {
-        List<String> ret           = new ArrayList<String>();
-        String  serviceName        = getServiceName();
-        String  serviceType		   = getServiceType();
-        Map<String,String> configs = getConfigs();
-        if(LOG.isDebugEnabled()) {
-            LOG.debug("==> RangerServiceOzone.lookupResource Context: (" + context + ")");
-        }
+        List<String>        ret         = new ArrayList<>();
+        String              serviceName = getServiceName();
+        String              serviceType = getServiceType();
+        Map<String, String> configs     = getConfigs();
+
+        LOG.debug("==> RangerServiceOzone.lookupResource Context: ({})", context);
+
         if (context != null) {
             try {
-                ret  = OzoneResourceMgr.getOzoneResources(serviceName, serviceType, configs,context);
+                ret = OzoneResourceMgr.getOzoneResources(serviceName, serviceType, configs, context);
             } catch (Exception e) {
-                LOG.error( "<==RangerServiceOzone.lookupResource Error : " + e);
+                LOG.error("<==RangerServiceOzone.lookupResource Error : ", e);
                 throw e;
             }
         }
-        if(LOG.isDebugEnabled()) {
-            LOG.debug("<== RangerServiceOzone.lookupResource Response: (" + ret + ")");
-        }
+
+        LOG.debug("<== RangerServiceOzone.lookupResource Response: ({})", ret);
+
         return ret;
     }
 
     @Override
     public List<RangerPolicy> getDefaultRangerPolicies() throws Exception {
-        if (LOG.isDebugEnabled()) {
-            LOG.debug("==> RangerServiceOzone.getDefaultRangerPolicies() ");
-        }
+        LOG.debug("==> RangerServiceOzone.getDefaultRangerPolicies() ");
 
         List<RangerPolicy> ret = super.getDefaultRangerPolicies();
 
-		for (RangerPolicy defaultPolicy : ret) {
-			if (defaultPolicy.getName().startsWith("all")) {
-                		RangerPolicyItem policyItemOwner = new RangerPolicyItem();
-                		policyItemOwner.setUsers(Collections.singletonList(RangerPolicyEngine.RESOURCE_OWNER));
-                		policyItemOwner.setAccesses(Collections.singletonList(new RangerPolicyItemAccess(ACCESS_TYPE_ALL)));
-                		policyItemOwner.setDelegateAdmin(true);
-                		defaultPolicy.addPolicyItem(policyItemOwner);
+        for (RangerPolicy defaultPolicy : ret) {
+            if (defaultPolicy.getName().startsWith("all")) {
+                RangerPolicyItem policyItemOwner = new RangerPolicyItem();
 
-                		if (StringUtils.isNotBlank(lookUpUser)) {
-					RangerPolicyItem policyItemForLookupUser = new RangerPolicyItem();
-					List<RangerPolicy.RangerPolicyItemAccess> accessListForLookupUser = new ArrayList<RangerPolicy.RangerPolicyItemAccess>();
-					accessListForLookupUser.add(new RangerPolicyItemAccess(ACCESS_TYPE_READ));
-					accessListForLookupUser.add(new RangerPolicyItemAccess(ACCESS_TYPE_WRITE));
-					accessListForLookupUser.add(new RangerPolicyItemAccess(ACCESS_TYPE_CREATE));
-					accessListForLookupUser.add(new RangerPolicyItemAccess(ACCESS_TYPE_LIST));
-					accessListForLookupUser.add(new RangerPolicyItemAccess(ACCESS_TYPE_DELETE));
-                    			accessListForLookupUser.add(new RangerPolicyItemAccess(ACCESS_TYPE_READ_ACL));
-                    			accessListForLookupUser.add(new RangerPolicyItemAccess(ACCESS_TYPE_WRITE_ACL));
-					accessListForLookupUser.add(new RangerPolicyItemAccess(ACCESS_TYPE_ALL));
-					policyItemForLookupUser.setUsers(Collections.singletonList(lookUpUser));
-					policyItemForLookupUser.setAccesses(accessListForLookupUser);
-					policyItemForLookupUser.setDelegateAdmin(false);
-					defaultPolicy.addPolicyItem(policyItemForLookupUser);
-				}
-			}
-		}	
-        if (LOG.isDebugEnabled()) {
-            LOG.debug("<== RangerServiceOzone.getDefaultRangerPolicies() : " + ret);
+                policyItemOwner.setUsers(Collections.singletonList(RangerPolicyEngine.RESOURCE_OWNER));
+                policyItemOwner.setAccesses(Collections.singletonList(new RangerPolicyItemAccess(ACCESS_TYPE_ALL)));
+                policyItemOwner.setDelegateAdmin(true);
+
+                defaultPolicy.addPolicyItem(policyItemOwner);
+
+                if (StringUtils.isNotBlank(lookUpUser)) {
+                    RangerPolicyItem             policyItemForLookupUser = new RangerPolicyItem();
+                    List<RangerPolicyItemAccess> accessListForLookupUser = new ArrayList<>();
+
+                    accessListForLookupUser.add(new RangerPolicyItemAccess(ACCESS_TYPE_READ));
+                    accessListForLookupUser.add(new RangerPolicyItemAccess(ACCESS_TYPE_WRITE));
+                    accessListForLookupUser.add(new RangerPolicyItemAccess(ACCESS_TYPE_CREATE));
+                    accessListForLookupUser.add(new RangerPolicyItemAccess(ACCESS_TYPE_LIST));
+                    accessListForLookupUser.add(new RangerPolicyItemAccess(ACCESS_TYPE_DELETE));
+                    accessListForLookupUser.add(new RangerPolicyItemAccess(ACCESS_TYPE_READ_ACL));
+                    accessListForLookupUser.add(new RangerPolicyItemAccess(ACCESS_TYPE_WRITE_ACL));
+                    accessListForLookupUser.add(new RangerPolicyItemAccess(ACCESS_TYPE_ALL));
+
+                    policyItemForLookupUser.setUsers(Collections.singletonList(lookUpUser));
+                    policyItemForLookupUser.setAccesses(accessListForLookupUser);
+                    policyItemForLookupUser.setDelegateAdmin(false);
+
+                    defaultPolicy.addPolicyItem(policyItemForLookupUser);
+                }
+            }
         }
+
+        LOG.debug("<== RangerServiceOzone.getDefaultRangerPolicies() : {}", ret);
+
         return ret;
     }
-
 }
diff --git a/plugin-ozone/src/main/java/org/apache/ranger/services/ozone/client/OzoneClient.java b/plugin-ozone/src/main/java/org/apache/ranger/services/ozone/client/OzoneClient.java
index 0bda6b6..6937776 100644
--- a/plugin-ozone/src/main/java/org/apache/ranger/services/ozone/client/OzoneClient.java
+++ b/plugin-ozone/src/main/java/org/apache/ranger/services/ozone/client/OzoneClient.java
@@ -29,30 +29,40 @@
 import org.slf4j.LoggerFactory;
 
 import javax.security.auth.Subject;
+
 import java.io.IOException;
 import java.security.PrivilegedExceptionAction;
-import java.util.*;
+import java.util.ArrayList;
+import java.util.HashMap;
+import java.util.Iterator;
+import java.util.List;
+import java.util.Map;
+import java.util.Set;
 
 public class OzoneClient extends BaseClient {
+    private static final Logger LOG = LoggerFactory.getLogger(OzoneClient.class);
 
-    private static final Logger LOG     = LoggerFactory.getLogger(OzoneClient.class);
-    private static final String ERR_MSG = "You can still save the repository and start creating policies, but you " +
-            "would not be able to use autocomplete for resource names. Check ranger_admin.log for more info.";
+    private static final String ERR_MSG = "You can still save the repository and start creating policies, but you would not be able to use autocomplete for resource names. Check ranger_admin.log for more info.";
 
-    private final OzoneConfiguration conf;
-    private org.apache.hadoop.ozone.client.OzoneClient ozoneClient = null;
+    private final OzoneConfiguration                         conf;
+    private       org.apache.hadoop.ozone.client.OzoneClient ozoneClient;
 
-    public OzoneClient(String serviceName, Map<String,String> connectionProperties) throws Exception{
-        super(serviceName,connectionProperties, "ozone-client");
+    public OzoneClient(String serviceName, Map<String, String> connectionProperties) throws Exception {
+        super(serviceName, connectionProperties, "ozone-client");
+
         conf = new OzoneConfiguration();
+
         Set<String> rangerInternalPropertyKeys = getConfigHolder().getRangerInternalPropertyKeys();
-        for (Map.Entry<String, String> entry: connectionProperties.entrySet())  {
+
+        for (Map.Entry<String, String> entry : connectionProperties.entrySet()) {
             String key   = entry.getKey();
             String value = entry.getValue();
+
             if (!rangerInternalPropertyKeys.contains(key) && value != null) {
                 conf.set(key, value);
             }
         }
+
         Subject.doAs(getLoginSubject(), (PrivilegedExceptionAction<Void>) () -> {
             String[] serviceIds = conf.getTrimmedStrings("ozone.om.service.ids", "ozone1");
             ozoneClient = OzoneClientFactory.getRpcClient(serviceIds[0], conf);
@@ -60,24 +70,56 @@ public OzoneClient(String serviceName, Map<String,String> connectionProperties)
         });
     }
 
+    public static Map<String, Object> connectionTest(String serviceName, Map<String, String> connectionProperties) throws Exception {
+        Map<String, Object> responseData       = new HashMap<>();
+        OzoneClient         connectionObj      = null;
+        boolean             connectivityStatus = false;
+        List<String>        testResult;
+
+        try {
+            connectionObj = new OzoneClient(serviceName, connectionProperties);
+            testResult    = connectionObj.getVolumeList("");
+
+            if (testResult != null && testResult.size() != 0) {
+                connectivityStatus = true;
+            }
+
+            if (connectivityStatus) {
+                String successMsg = "ConnectionTest Successful";
+
+                generateResponseDataMap(true, successMsg, successMsg, null, null, responseData);
+            } else {
+                String failureMsg = "Unable to retrieve any volumes using given parameters.";
+                String errorMsg   = failureMsg + ERR_MSG;
+
+                generateResponseDataMap(false, failureMsg, errorMsg, null, null, responseData);
+            }
+        } finally {
+            if (connectionObj != null) {
+                connectionObj.close();
+            }
+        }
+
+        return responseData;
+    }
+
     public void close() {
         try {
             ozoneClient.close();
         } catch (IOException e) {
             LOG.error("Unable to close Ozone Client connection", e);
         }
-
     }
 
     public List<String> getVolumeList(String volumePrefix) {
-        if (LOG.isDebugEnabled()) {
-            LOG.debug("==> OzoneClient getVolume volumePrefix : " + volumePrefix);
-        }
+        LOG.debug("==> OzoneClient getVolume volumePrefix : {}", volumePrefix);
 
         List<String> ret = new ArrayList<>();
+
         try {
             if (ozoneClient != null) {
                 Iterator<? extends OzoneVolume> ozoneVolList = ozoneClient.getObjectStore().listVolumes(volumePrefix);
+
                 if (ozoneVolList != null) {
                     while (ozoneVolList.hasNext()) {
                         ret.add(ozoneVolList.next().getName());
@@ -86,25 +128,24 @@ public List<String> getVolumeList(String volumePrefix) {
             }
         } catch (IOException e) {
             LOG.error("Unable to get Volume List");
-            if (LOG.isDebugEnabled()) {
-                LOG.debug("<== OzoneClient.getVolumeList() Error : " , e);
-            }
+            LOG.debug("<== OzoneClient.getVolumeList() Error : ", e);
         }
-        if (LOG.isDebugEnabled()) {
-            LOG.debug("<== OzoneClient.getVolumeList(): " + ret);
-        }
+
+        LOG.debug("<== OzoneClient.getVolumeList(): {}", ret);
+
         return ret;
     }
 
     public List<String> getBucketList(String bucketPrefix, List<String> finalVolumeList) {
-        if (LOG.isDebugEnabled()) {
-            LOG.debug("==> OzoneClient getBucketList bucketPrefix : " + bucketPrefix);
-        }
+        LOG.debug("==> OzoneClient getBucketList bucketPrefix : {}", bucketPrefix);
+
         List<String> ret = new ArrayList<>();
+
         try {
-            if (ozoneClient != null && finalVolumeList != null && !finalVolumeList.isEmpty()){
+            if (ozoneClient != null && finalVolumeList != null && !finalVolumeList.isEmpty()) {
                 for (String ozoneVol : finalVolumeList) {
                     Iterator<? extends OzoneBucket> ozoneBucketList = ozoneClient.getObjectStore().getVolume(ozoneVol).listBuckets(bucketPrefix);
+
                     if (ozoneBucketList != null) {
                         while (ozoneBucketList.hasNext()) {
                             ret.add(ozoneBucketList.next().getName());
@@ -114,30 +155,31 @@ public List<String> getBucketList(String bucketPrefix, List<String> finalVolumeL
             }
         } catch (IOException e) {
             LOG.error("Unable to get Volume List");
-            if (LOG.isDebugEnabled()) {
-                LOG.debug("<== OzoneClient.getVolumeList() Error : " , e);
-            }
+            LOG.debug("<== OzoneClient.getVolumeList() Error : ", e);
         }
-        if (LOG.isDebugEnabled()) {
-            LOG.debug("<== OzoneClient.getVolumeList(): " + ret);
-        }
+
+        LOG.debug("<== OzoneClient.getVolumeList(): {}", ret);
+
         return ret;
     }
 
     public List<String> getKeyList(String keyPrefix, List<String> finalVolumeList, List<String> finalBucketList) {
-        if (LOG.isDebugEnabled()) {
-            LOG.debug("==> OzoneClient getKeyList keyPrefix : " + keyPrefix);
-        }
+        LOG.debug("==> OzoneClient getKeyList keyPrefix : {}", keyPrefix);
+
         List<String> ret = new ArrayList<>();
+
         try {
             if (ozoneClient != null && finalVolumeList != null && !finalVolumeList.isEmpty()) {
                 for (String ozoneVol : finalVolumeList) {
                     Iterator<? extends OzoneBucket> ozoneBucketIterator = ozoneClient.getObjectStore().getVolume(ozoneVol).listBuckets(null);
+
                     if (ozoneBucketIterator != null) {
                         while (ozoneBucketIterator.hasNext()) {
                             OzoneBucket currentBucket = ozoneBucketIterator.next();
+
                             if (finalBucketList.contains(currentBucket.getName())) {
                                 Iterator<? extends OzoneKey> ozoneKeyIterator = currentBucket.listKeys(keyPrefix);
+
                                 if (ozoneKeyIterator != null) {
                                     while (ozoneKeyIterator.hasNext()) {
                                         ret.add(ozoneKeyIterator.next().getName());
@@ -150,44 +192,11 @@ public List<String> getKeyList(String keyPrefix, List<String> finalVolumeList, L
             }
         } catch (IOException e) {
             LOG.error("Unable to get Volume List");
-            if (LOG.isDebugEnabled()) {
-                LOG.debug("<== OzoneClient.getVolumeList() Error : " , e);
-            }
+            LOG.debug("<== OzoneClient.getVolumeList() Error : ", e);
         }
-        if (LOG.isDebugEnabled()) {
-            LOG.debug("<== OzoneClient.getVolumeList(): " + ret);
-        }
+
+        LOG.debug("<== OzoneClient.getVolumeList(): {}", ret);
+
         return ret;
     }
-
-    public static Map<String, Object> connectionTest(String serviceName,
-                                                     Map<String, String> connectionProperties) throws Exception {
-        Map<String, Object> responseData = new HashMap<>();
-        OzoneClient connectionObj = null;
-        boolean connectivityStatus = false;
-        List<String> testResult;
-
-        try {
-            connectionObj = new OzoneClient(serviceName, connectionProperties);
-            testResult    = connectionObj.getVolumeList("");
-            if (testResult != null && testResult.size() != 0) {
-                connectivityStatus = true;
-            }
-            if (connectivityStatus) {
-                String successMsg = "ConnectionTest Successful";
-                generateResponseDataMap(true, successMsg, successMsg,
-                        null, null, responseData);
-            } else {
-                String failureMsg = "Unable to retrieve any volumes using given parameters.";
-                generateResponseDataMap(false, failureMsg, failureMsg + ERR_MSG,
-                        null, null, responseData);
-            }
-        } finally {
-            if (connectionObj != null) {
-                connectionObj.close();
-            }
-        }
-
-        return responseData;
-    }
 }
diff --git a/plugin-ozone/src/main/java/org/apache/ranger/services/ozone/client/OzoneConnectionMgr.java b/plugin-ozone/src/main/java/org/apache/ranger/services/ozone/client/OzoneConnectionMgr.java
index 54dbc7f..a88b557 100644
--- a/plugin-ozone/src/main/java/org/apache/ranger/services/ozone/client/OzoneConnectionMgr.java
+++ b/plugin-ozone/src/main/java/org/apache/ranger/services/ozone/client/OzoneConnectionMgr.java
@@ -32,33 +32,33 @@
 public class OzoneConnectionMgr {
     private static final Logger LOG = LoggerFactory.getLogger(OzoneConnectionMgr.class);
 
-    protected ConcurrentMap<String, OzoneClient>    ozoneConnectionCache;
-    protected ConcurrentMap<String, Boolean>        repoConnectStatusMap;
+    protected ConcurrentMap<String, OzoneClient> ozoneConnectionCache;
+    protected ConcurrentMap<String, Boolean>     repoConnectStatusMap;
 
-
-    public	OzoneConnectionMgr() {
-        ozoneConnectionCache = new ConcurrentHashMap<String, OzoneClient>();
-        repoConnectStatusMap = new ConcurrentHashMap<String, Boolean>();
+    public OzoneConnectionMgr() {
+        ozoneConnectionCache = new ConcurrentHashMap<>();
+        repoConnectStatusMap = new ConcurrentHashMap<>();
     }
 
-
-    public OzoneClient getOzoneConnection(final String serviceName, final String serviceType, final Map<String,String> configs) {
-        OzoneClient ozoneClient  = null;
+    public OzoneClient getOzoneConnection(final String serviceName, final String serviceType, final Map<String, String> configs) {
+        OzoneClient ozoneClient = null;
 
         if (serviceType != null) {
             // get it from the cache
             ozoneClient = ozoneConnectionCache.get(serviceName);
+
             if (ozoneClient == null) {
                 if (configs != null) {
-
                     final Callable<OzoneClient> connectOzone = () -> new OzoneClient(serviceName, configs);
+
                     try {
                         ozoneClient = TimedEventUtil.timedTask(connectOzone, 5, TimeUnit.SECONDS);
-                    } catch(Exception e){
-                        LOG.error("Error connecting ozone repository : " + serviceName +" using config : "+ configs, e);
+                    } catch (Exception e) {
+                        LOG.error("Error connecting ozone repository: {} using config: {}", serviceName, configs, e);
                     }
 
                     OzoneClient oldClient;
+
                     if (ozoneClient != null) {
                         oldClient = ozoneConnectionCache.putIfAbsent(serviceName, ozoneClient);
                     } else {
@@ -70,28 +70,36 @@ public OzoneClient getOzoneConnection(final String serviceName, final String ser
                         if (ozoneClient != null) {
                             ozoneClient.close();
                         }
+
                         ozoneClient = oldClient;
                     }
+
                     repoConnectStatusMap.put(serviceName, true);
                 } else {
-                    LOG.error("Connection Config not defined for asset :" + serviceName, new Throwable());
+                    String message = String.format("Connection Config not defined for asset: %s", serviceName);
+
+                    LOG.error(message, new IllegalStateException(message));
                 }
             } else {
                 try {
                     ozoneClient.getVolumeList(null);
-                } catch(Exception e) {
+                } catch (Exception e) {
                     ozoneConnectionCache.remove(serviceName);
                     /*
                      * There is a possibility that some other thread is also using this connection that we are going to close but
                      * presumably the connection is bad which is why we are closing it, so damage should not be much.
                      */
                     ozoneClient.close();
-                    ozoneClient = getOzoneConnection(serviceName,serviceType,configs);
+
+                    ozoneClient = getOzoneConnection(serviceName, serviceType, configs);
                 }
             }
         } else {
-            LOG.error("Asset not found with name "+serviceName, new Throwable());
+            String message = String.format("Asset not found with name: %s", serviceName);
+
+            LOG.error(message, new IllegalStateException(message));
         }
+
         return ozoneClient;
     }
 }
diff --git a/plugin-ozone/src/main/java/org/apache/ranger/services/ozone/client/OzoneResourceMgr.java b/plugin-ozone/src/main/java/org/apache/ranger/services/ozone/client/OzoneResourceMgr.java
index fa84312..bec2138 100644
--- a/plugin-ozone/src/main/java/org/apache/ranger/services/ozone/client/OzoneResourceMgr.java
+++ b/plugin-ozone/src/main/java/org/apache/ranger/services/ozone/client/OzoneResourceMgr.java
@@ -31,59 +31,54 @@
 import java.util.concurrent.TimeUnit;
 
 public class OzoneResourceMgr {
-
     private static final Logger LOG = LoggerFactory.getLogger(OzoneResourceMgr.class);
 
-    private static final String VOLUME     = "volume";
-    private static final String BUCKET     = "bucket";
-    private static final String KEY        = "key";
+    private static final String VOLUME = "volume";
+    private static final String BUCKET = "bucket";
+    private static final String KEY    = "key";
 
+    private OzoneResourceMgr() {
+        throw new UnsupportedOperationException("OzoneResourceMgr cannot be instantiated!");
+    }
 
     public static Map<String, Object> connectionTest(String serviceName, Map<String, String> configs) throws Exception {
-        Map<String, Object> ret = null;
+        Map<String, Object> ret;
 
-        if(LOG.isDebugEnabled()) {
-            LOG.debug("==> OzoneResourceMgr.connectionTest ServiceName: "+ serviceName + "Configs" + configs );
-        }
+        LOG.debug("==> OzoneResourceMgr.connectionTest ServiceName: {} Configs: {}", serviceName, configs);
 
         try {
             ret = OzoneClient.connectionTest(serviceName, configs);
         } catch (HadoopException e) {
-            LOG.error("<== OzoneResourceMgr.connectionTest Error: " + e);
+            LOG.error("<== OzoneResourceMgr.connectionTest Error: ", e);
             throw e;
         }
 
-        if(LOG.isDebugEnabled()) {
-            LOG.debug("<== OzoneResourceMgr.connectionTest Result : "+ ret  );
-        }
+        LOG.debug("<== OzoneResourceMgr.connectionTest Result : {}", ret);
 
         return ret;
     }
 
-    public static List<String> getOzoneResources(String serviceName, String serviceType, Map<String, String> configs, ResourceLookupContext context) throws Exception  {
-
-        String userInput                       = context.getUserInput();
-        String resource	                       = context.getResourceName();
+    public static List<String> getOzoneResources(String serviceName, String serviceType, Map<String, String> configs, ResourceLookupContext context) throws Exception {
+        String                    userInput    = context.getUserInput();
+        String                    resource     = context.getResourceName();
         Map<String, List<String>> resourceMap  = context.getResources();
-        List<String> resultList 	           = null;
-        List<String> volumeList                = null;
-        List<String> bucketList	               = null;
-        List<String> keyList	               = null;
-        String volumePrefix                    = null;
-        String bucketPrefix	                   = null;
-        String keyPrefix	                   = null;
+        List<String>              resultList   = null;
+        List<String>              volumeList   = null;
+        List<String>              bucketList   = null;
+        List<String>              keyList      = null;
+        String                    volumePrefix = null;
+        String                    bucketPrefix = null;
+        String                    keyPrefix    = null;
 
+        LOG.debug("<== OzoneResourceMgr.getOzoneResources()  UserInput: {} resource: {} resourceMap: {}", userInput, resource, resourceMap);
 
-        if(LOG.isDebugEnabled()) {
-            LOG.debug("<== OzoneResourceMgr.getOzoneResources()  UserInput: \""+ userInput  + "\" resource : " + resource + " resourceMap: "  + resourceMap);
-        }
-
-        if ( userInput != null && resource != null) {
-            if ( resourceMap != null  && !resourceMap.isEmpty() ) {
+        if (userInput != null && resource != null) {
+            if (resourceMap != null && !resourceMap.isEmpty()) {
                 volumeList = resourceMap.get(VOLUME);
                 bucketList = resourceMap.get(BUCKET);
-                keyList = resourceMap.get(KEY);
+                keyList    = resourceMap.get(KEY);
             }
+
             switch (resource.trim().toLowerCase()) {
                 case VOLUME:
                     volumePrefix = userInput;
@@ -92,7 +87,7 @@ public static List<String> getOzoneResources(String serviceName, String serviceT
                     bucketPrefix = userInput;
                     break;
                 case KEY:
-                    keyPrefix    = userInput;
+                    keyPrefix = userInput;
                     break;
                 default:
                     break;
@@ -101,63 +96,32 @@ public static List<String> getOzoneResources(String serviceName, String serviceT
 
         if (serviceName != null && userInput != null) {
             try {
-
-                if(LOG.isDebugEnabled()) {
-                    LOG.debug("==> OzoneResourceMgr.getOzoneResources() UserInput: "+ userInput  + " configs: " + configs + " volumeList: "  + volumeList + " bucketList: "
-                            + bucketList + " keyList: " + keyList );
-                }
+                LOG.debug("==> OzoneResourceMgr.getOzoneResources() UserInput: {} configs: {} volumeList: {} bucketList: {}  keyList: {}", userInput, configs, volumeList, bucketList, keyList);
 
                 final OzoneClient ozoneClient = new OzoneConnectionMgr().getOzoneConnection(serviceName, serviceType, configs);
 
                 Callable<List<String>> callableObj = null;
-                final String finalVolPrefix;
-                final String finalBucketPrefix;
-                final String finalKeyPrefix;
+                final String           finalVolPrefix;
+                final String           finalBucketPrefix;
+                final String           finalKeyPrefix;
 
                 final List<String> finalvolumeList = volumeList;
                 final List<String> finalbucketList = bucketList;
 
-                if ( ozoneClient != null) {
-                    if ( volumePrefix != null
-                            && !volumePrefix.isEmpty()){
-                        // get the DBList for given Input
+                if (ozoneClient != null) {
+                    if (volumePrefix != null && !volumePrefix.isEmpty()) {
                         finalVolPrefix = volumePrefix;
-                        callableObj = new Callable<List<String>>() {
-                            @Override
-                            public List<String> call() {
-                                return ozoneClient.getVolumeList(finalVolPrefix);
-                            }
-                        };
-                    } else if ( bucketPrefix != null
-                            && !bucketPrefix.isEmpty()) {
-                        // get  ColumnList for given Input
+                        callableObj    = () -> ozoneClient.getVolumeList(finalVolPrefix);
+                    } else if (bucketPrefix != null && !bucketPrefix.isEmpty()) {
                         finalBucketPrefix = bucketPrefix;
-                        callableObj = new Callable<List<String>>() {
-
-                            @Override
-                            public List<String> call() {
-                                return ozoneClient.getBucketList(finalBucketPrefix,
-                                        finalvolumeList);
-                            }
-                        };
-                    } else if ( keyPrefix != null
-                            && !keyPrefix.isEmpty()) {
-                        // get  ColumnList for given Input
-                       finalKeyPrefix = keyPrefix;
-
-                        callableObj = new Callable<List<String>>() {
-                            @Override
-                            public List<String> call() {
-                                return ozoneClient.getKeyList(finalKeyPrefix,
-                                        finalvolumeList,
-                                        finalbucketList);
-                            }
-                        };
+                        callableObj       = () -> ozoneClient.getBucketList(finalBucketPrefix, finalvolumeList);
+                    } else if (keyPrefix != null && !keyPrefix.isEmpty()) {
+                        finalKeyPrefix = keyPrefix;
+                        callableObj    = () -> ozoneClient.getKeyList(finalKeyPrefix, finalvolumeList, finalbucketList);
                     }
                     if (callableObj != null) {
                         synchronized (ozoneClient) {
-                            resultList = TimedEventUtil.timedTask(callableObj, 5,
-                                    TimeUnit.SECONDS);
+                            resultList = TimedEventUtil.timedTask(callableObj, 5, TimeUnit.SECONDS);
                         }
                     } else {
                         LOG.error("Could not initiate at timedTask");
@@ -169,13 +133,8 @@ public List<String> call() {
             }
         }
 
-        if(LOG.isDebugEnabled()) {
-            LOG.debug("<== OzoneResourceMgr.getOzoneResources() UserInput: "+ userInput  + " configs: " + configs + " volumeList: "  + volumeList + " bucketList: "
-                    + bucketList + " keyList: " + keyList + "Result :" + resultList );
+        LOG.debug("<== OzoneResourceMgr.getOzoneResources() UserInput: {} configs: {} volumeList: {} bucketList: {} keyList: {} Result: {}", userInput, configs, volumeList, bucketList, keyList, resultList);
 
-        }
         return resultList;
-
     }
-
 }