Fixed literal string comparison.

This line is in the form of
String str = ...
str.equals("someOtherString");
//or
str.compareTo("someOtherString");

A NullPointerException may occur if the String variable str is null. If instead the code was restructured to
String str = ...
"someOtherString".equals(str);
//or
"someOtherString".compareTo(str);
that is, call equals() or compareTo() on the string literal, passing the variable as an argument, this exception could never happen as both equals() and compareTo() check for null.

components/apimgt-extensions/org.wso2.carbon.apimgt.application.extension.api/src/main/java/org/wso2/carbon/apimgt/application/extension/api/ApiApplicationRegistrationServiceImpl.java

@@ -22,13 +22,13 @@ import org.apache.commons.logging.Log;
 import org.apache.commons.logging.LogFactory;
 import org.json.simple.JSONObject;
 import org.wso2.carbon.apimgt.application.extension.APIManagementProviderService;
+import org.wso2.carbon.apimgt.application.extension.api.util.APIUtil;
 import org.wso2.carbon.apimgt.application.extension.api.util.RegistrationProfile;
 import org.wso2.carbon.apimgt.application.extension.constants.ApiApplicationConstants;
 import org.wso2.carbon.apimgt.application.extension.dto.ApiApplicationKey;
 import org.wso2.carbon.apimgt.application.extension.exception.APIManagerException;
 import org.wso2.carbon.base.MultitenantConstants;
 import org.wso2.carbon.context.PrivilegedCarbonContext;
-import org.wso2.carbon.apimgt.application.extension.api.util.APIUtil;
 import org.wso2.carbon.user.api.UserStoreException;
 
 import javax.ws.rs.DELETE;
@@ -46,7 +46,7 @@ public class ApiApplicationRegistrationServiceImpl implements ApiApplicationRegi
     public Response register(@QueryParam("tenantDomain") String tenantDomain,
                              @QueryParam("applicationName") String applicationName) {
         String authenticatedTenantDomain = PrivilegedCarbonContext.getThreadLocalCarbonContext().getTenantDomain();
-        if (!authenticatedTenantDomain.equals(MultitenantConstants.SUPER_TENANT_DOMAIN_NAME)) {
+        if (!MultitenantConstants.SUPER_TENANT_DOMAIN_NAME.equals(authenticatedTenantDomain)) {
             return Response.status(Response.Status.NOT_ACCEPTABLE).build();
         }
         try {

components/apimgt-extensions/org.wso2.carbon.apimgt.application.extension/src/main/java/org/wso2/carbon/apimgt/application/extension/APIManagementProviderServiceImpl.java

@@ -23,12 +23,7 @@ import org.apache.commons.logging.LogFactory;
 import org.json.simple.JSONObject;
 import org.wso2.carbon.apimgt.api.APIConsumer;
 import org.wso2.carbon.apimgt.api.APIManagementException;
-import org.wso2.carbon.apimgt.api.model.API;
+import org.wso2.carbon.apimgt.api.model.*;
-import org.wso2.carbon.apimgt.api.model.APIIdentifier;
-import org.wso2.carbon.apimgt.api.model.APIKey;
-import org.wso2.carbon.apimgt.api.model.Application;
-import org.wso2.carbon.apimgt.api.model.SubscribedAPI;
-import org.wso2.carbon.apimgt.api.model.Subscriber;
 import org.wso2.carbon.apimgt.application.extension.constants.ApiApplicationConstants;
 import org.wso2.carbon.apimgt.application.extension.dto.ApiApplicationKey;
 import org.wso2.carbon.apimgt.application.extension.exception.APIManagerException;
@@ -415,7 +410,7 @@ public class APIManagementProviderServiceImpl implements APIManagementProviderSe
             int applicationId = createApplication(apiConsumer, apiApplicationName, username, groupId);
             String tenantDomain = MultitenantUtils.getTenantDomain(username);
             Set<API> userVisibleAPIs = apiConsumer.getAllPublishedAPIs(tenantDomain);
-            if (!tenantDomain.equals(MultitenantConstants.SUPER_TENANT_DOMAIN_NAME)) {
+            if (!MultitenantConstants.SUPER_TENANT_DOMAIN_NAME.equals(tenantDomain)) {
                 userVisibleAPIs.addAll(apiConsumer.getAllPublishedAPIs(MultitenantConstants.SUPER_TENANT_DOMAIN_NAME));
             }
             Subscriber subscriber = apiConsumer.getSubscriber(username);
@@ -443,7 +438,7 @@ public class APIManagementProviderServiceImpl implements APIManagementProviderSe
         try {
             APIConsumer apiConsumer = APIManagerFactory.getInstance().getAPIConsumer(username);
             loginInfoJsonObj.put("user", username);
-            if (tenantDomain.equals(MultitenantConstants.SUPER_TENANT_DOMAIN_NAME)) {
+            if (MultitenantConstants.SUPER_TENANT_DOMAIN_NAME.equals(tenantDomain)) {
                 loginInfoJsonObj.put("isSuperTenant", true);
             } else {
                 loginInfoJsonObj.put("isSuperTenant", false);

components/apimgt-extensions/org.wso2.carbon.apimgt.application.extension/src/main/java/org/wso2/carbon/apimgt/application/extension/util/APIManagerUtil.java

@@ -37,7 +37,7 @@ public final class APIManagerUtil {
      */
     public static int getTenantId(String tenantDomain) throws APIManagerException {
         try {
-            if (tenantDomain.equals(MultitenantConstants.SUPER_TENANT_DOMAIN_NAME)) {
+            if (MultitenantConstants.SUPER_TENANT_DOMAIN_NAME.equals(tenantDomain)) {
                 return MultitenantConstants.SUPER_TENANT_ID;
             }
             TenantManager tenantManager = APIApplicationManagerExtensionDataHolder.getInstance().getTenantManager();

components/apimgt-extensions/org.wso2.carbon.apimgt.webapp.publisher/src/main/java/org/wso2/carbon/apimgt/webapp/publisher/APIPublisherUtil.java

@@ -36,10 +36,10 @@ import java.util.*;
 
 public class APIPublisherUtil {
 
-    private static final Log log = LogFactory.getLog(APIPublisherUtil.class);
-    private static final String DEFAULT_API_VERSION = "1.0.0";
     public static final String API_VERSION_PARAM = "{version}";
     public static final String API_PUBLISH_ENVIRONMENT = "Production and Sandbox";
+    private static final Log log = LogFactory.getLog(APIPublisherUtil.class);
+    private static final String DEFAULT_API_VERSION = "1.0.0";
     private static final String API_CONFIG_DEFAULT_VERSION = "1.0.0";
     private static final String PARAM_MANAGED_API_ENDPOINT = "managed-api-endpoint";
     private static final String PARAM_MANAGED_API_OWNER = "managed-api-owner";
@@ -242,7 +242,7 @@ public class APIPublisherUtil {
                 MultitenantConstants.SUPER_TENANT_DOMAIN_NAME;
         apiConfig.setTenantDomain(tenantDomain);
         String contextTemplate = context + "/" + APIConstants.VERSION_PLACEHOLDER;
-        if (!tenantDomain.equals(MultitenantConstants.SUPER_TENANT_DOMAIN_NAME)) {
+        if (!MultitenantConstants.SUPER_TENANT_DOMAIN_NAME.equals(tenantDomain)) {
             contextTemplate = context + "/t/" + tenantDomain + "/" + APIConstants.VERSION_PLACEHOLDER;
         }
         apiConfig.setContextTemplate(contextTemplate);

components/apimgt-extensions/org.wso2.carbon.apimgt.webapp.publisher/src/main/java/org/wso2/carbon/apimgt/webapp/publisher/lifecycle/util/AnnotationProcessor.java

@@ -63,11 +63,10 @@ public class AnnotationProcessor {
     private static final String HTTP_PORT = "httpPort";
     private static final String STRING_ARR = "string_arr";
     private static final String STRING = "string";
-
+    Class<API> apiClazz;
     private StandardContext context;
     private Method[] pathClazzMethods;
     private Class<Path> pathClazz;
-    Class<API> apiClazz;
     private ClassLoader classLoader;
     private ServletContext servletContext;
 
@@ -319,7 +318,7 @@ public class AnnotationProcessor {
      * @return
      */
     private String makeContextURLReady(String context) {
-        if (context != null && !context.equalsIgnoreCase("")) {
+        if (context != null && context.length() > 0) {
             if (context.startsWith("/")) {
                 return context;
             } else {

components/device-mgt/org.wso2.carbon.device.mgt.analytics.data.publisher/src/main/java/org/wso2/carbon/device/mgt/analytics/data/publisher/DeviceDataPublisher.java

@@ -60,6 +60,10 @@ public class DeviceDataPublisher {
     private static Map<String, DataPublisher> dataPublisherMap;
     private static DeviceDataPublisher deviceDataPublisher;
 
+    public DeviceDataPublisher() {
+        dataPublisherMap = new ConcurrentHashMap<>();
+    }
+
     public static DeviceDataPublisher getInstance() {
         if (deviceDataPublisher == null) {
             synchronized (DeviceDataPublisher.class) {
@@ -71,10 +75,6 @@ public class DeviceDataPublisher {
         return deviceDataPublisher;
     }
 
-    public DeviceDataPublisher() {
-        dataPublisherMap = new ConcurrentHashMap<>();
-    }
-
     /**
      * this return the data publisher for the tenant.
      *
@@ -95,7 +95,7 @@ public class DeviceDataPublisher {
             String analyticsServerUrlGroups = analyticsConfig.getReceiverServerUrl();
             String analyticsServerUsername = analyticsConfig.getAdminUsername();
             String analyticsServerPassword = analyticsConfig.getAdminPassword();
-            if (!tenantDomain.equals(MultitenantConstants.SUPER_TENANT_DOMAIN_NAME)) {
+            if (!MultitenantConstants.SUPER_TENANT_DOMAIN_NAME.equals(tenantDomain)) {
                 int tenantId = CarbonContext.getThreadLocalCarbonContext().getTenantId();
                 String userInfo[] = getAnalyticsServerUserInfo(tenantId);
                 if (userInfo != null) {

components/device-mgt/org.wso2.carbon.device.mgt.api/src/main/java/org/wso2/carbon/device/mgt/jaxrs/service/impl/RoleManagementServiceImpl.java

@@ -125,11 +125,11 @@ public class RoleManagementServiceImpl implements RoleManagementService {
         UIPermissionNode[] deviceMgtPermissions = new UIPermissionNode[2];
 
         for (UIPermissionNode permissionNode : rolePermissions.getNodeList()) {
-            if (permissionNode.getResourcePath().equals("/permission/admin")) {
+            if ("/permission/admin".equals(permissionNode.getResourcePath())) {
                 for (UIPermissionNode node : permissionNode.getNodeList()) {
-                    if (node.getResourcePath().equals("/permission/admin/device-mgt")) {
+                    if ("/permission/admin/device-mgt".equals(node.getResourcePath())) {
                         deviceMgtPermissions[0] = node;
-                    } else if (node.getResourcePath().equals("/permission/admin/login")) {
+                    } else if ("/permission/admin/login".equals(node.getResourcePath())) {
                         deviceMgtPermissions[1] = node;
                     }
                 }

components/device-mgt/org.wso2.carbon.device.mgt.core/src/main/java/org/wso2/carbon/device/mgt/core/search/mgt/impl/QueryBuilderImpl.java

@@ -47,8 +47,7 @@ public class QueryBuilderImpl implements QueryBuilder {
         Condition locCondition = new Condition();
 
         if (conditions.size() == 1) {
-
+            if (Constants.LOCATION.equalsIgnoreCase(conditions.get(0).getKey())) {
-            if (conditions.get(0).getKey().equalsIgnoreCase(Constants.LOCATION)) {
                 locCondition = conditions.get(0);
             } else if (Utils.checkDeviceDetailsColumns(conditions.get(0).getKey()) ||
                     Utils.checkDeviceLocationColumns(conditions.get(0).getKey())) {
@@ -58,7 +57,7 @@ public class QueryBuilderImpl implements QueryBuilder {
             }
         } else {
             for (Condition con : conditions) {
-                if (con.getKey().equalsIgnoreCase(Constants.LOCATION)) {
+                if (Constants.LOCATION.equalsIgnoreCase(con.getKey())) {
                     locCondition = con;
                 } else if (Utils.checkDeviceDetailsColumns(con.getKey()) ||
                         Utils.checkDeviceLocationColumns(con.getKey())) {

components/device-mgt/org.wso2.carbon.device.mgt.core/src/main/java/org/wso2/carbon/device/mgt/core/util/DeviceManagerUtil.java

@@ -227,7 +227,7 @@ public final class DeviceManagerUtil {
      */
     public static int getTenantId(String tenantDomain) throws DeviceManagementException {
         try {
-            if (tenantDomain.equals(MultitenantConstants.SUPER_TENANT_DOMAIN_NAME)) {
+            if (MultitenantConstants.SUPER_TENANT_DOMAIN_NAME.equals(tenantDomain)) {
                 return MultitenantConstants.SUPER_TENANT_ID;
             }
             TenantManager tenantManager = DeviceManagementDataHolder.getInstance().getTenantManager();

components/policy-mgt/org.wso2.carbon.complex.policy.decision.point/src/main/java/org/wso2/carbon/policy/evaluator/FeatureFilterImpl.java

@@ -67,25 +67,25 @@ public class FeatureFilterImpl implements FeatureFilter {
         for (FeatureRules rule : featureRulesList) {
             String ruleName = rule.getEvaluationCriteria();
             String featureName = rule.getName();
-            if (ruleName.equalsIgnoreCase(Constants.DENY_OVERRIDES)) {
+            if (Constants.DENY_OVERRIDES.equalsIgnoreCase(ruleName)) {
                 getDenyOverridesFeatures(featureName, featureList, effectiveFeatureList);
             }
-            if (ruleName.equalsIgnoreCase(Constants.PERMIT_OVERRIDES)) {
+            if (Constants.PERMIT_OVERRIDES.equalsIgnoreCase(ruleName)) {
                 getPermitOverridesFeatures(featureName, featureList, effectiveFeatureList);
             }
-            if (ruleName.equalsIgnoreCase(Constants.FIRST_APPLICABLE)) {
+            if (Constants.FIRST_APPLICABLE.equalsIgnoreCase(ruleName)) {
                 getFirstApplicableFeatures(featureName, featureList, effectiveFeatureList);
             }
-            if (ruleName.equalsIgnoreCase(Constants.LAST_APPLICABLE)) {
+            if (Constants.LAST_APPLICABLE.equalsIgnoreCase(ruleName)) {
                 getLastApplicableFeatures(featureName, featureList, effectiveFeatureList);
             }
-            if (ruleName.equalsIgnoreCase(Constants.ALL_APPLICABLE)) {
+            if (Constants.ALL_APPLICABLE.equalsIgnoreCase(ruleName)) {
                 getAllApplicableFeatures(featureName, featureList, effectiveFeatureList);
             }
-            if (ruleName.equalsIgnoreCase(Constants.HIGHEST_APPLICABLE)) {
+            if (Constants.HIGHEST_APPLICABLE.equalsIgnoreCase(ruleName)) {
                 getHighestApplicableFeatures(featureName, featureList, effectiveFeatureList);
             }
-            if (ruleName.equalsIgnoreCase(Constants.LOWEST_APPLICABLE)) {
+            if (Constants.LOWEST_APPLICABLE.equalsIgnoreCase(ruleName)) {
                 getLowestApplicableFeatures(featureName, featureList, effectiveFeatureList);
             }
         }

components/policy-mgt/org.wso2.carbon.policy.mgt.core/src/main/java/org/wso2/carbon/policy/mgt/core/impl/ComplianceDecisionPointImpl.java

@@ -253,7 +253,7 @@ public class ComplianceDecisionPointImpl implements ComplianceDecisionPoint {
         Policy policy = complianceData.getPolicy();
         String compliance = this.getNoneComplianceRule(policy);
 
-        if (compliance.equals("")) {
+        if ("".equals(compliance)) {
             String msg = "Compliance rule is empty for the policy " + policy.getPolicyName() + ". Therefore " +
                     "Monitoring Engine cannot run.";
             throw new PolicyComplianceException(msg);

components/policy-mgt/org.wso2.carbon.policy.mgt.core/src/main/java/org/wso2/carbon/policy/mgt/core/util/PolicyManagerUtil.java

@@ -203,7 +203,7 @@ public class PolicyManagerUtil {
 
             if (configuration != null && !configuration.isEmpty()) {
                 for (ConfigurationEntry cEntry : configuration) {
-                    if (cEntry.getName().equalsIgnoreCase(MONITORING_FREQUENCY)) {
+                    if (MONITORING_FREQUENCY.equalsIgnoreCase(cEntry.getName())) {
                         if (cEntry.getValue() == null) {
                             throw new PolicyManagementException("Invalid value, i.e. '" + cEntry.getValue() +
                                     "', is configured as the monitoring frequency");

components/webapp-authenticator-framework/org.wso2.carbon.webapp.authenticator.framework/src/main/java/org/wso2/carbon/webapp/authenticator/framework/WebappAuthenticationValve.java

@@ -105,7 +105,7 @@ public class WebappAuthenticationValve extends CarbonTomcatValve {
                 ctx = tokenizer.nextToken();
             }
         }
-        return (ctx.equalsIgnoreCase("carbon") || ctx.equalsIgnoreCase("services"));
+        return ("carbon".equalsIgnoreCase(ctx) || "services".equalsIgnoreCase(ctx));
     }
 
     private boolean isNonSecuredEndPoint(Request request) {
@@ -132,10 +132,7 @@ public class WebappAuthenticationValve extends CarbonTomcatValve {
                 }
             }
         }
-        if (nonSecuredEndpoints.containsKey(uri)) {
+        return nonSecuredEndpoints.containsKey(uri);
-            return true;
-        }
-        return false;
     }
 
     private void processRequest(Request request, Response response, CompositeValve compositeValve,

components/webapp-authenticator-framework/org.wso2.carbon.webapp.authenticator.framework/src/main/java/org/wso2/carbon/webapp/authenticator/framework/authenticator/JWTAuthenticator.java

@@ -65,6 +65,13 @@ public class JWTAuthenticator implements WebappAuthenticator {
     private static final Map<String, PublicKey> publicKeyHolder = new HashMap<>();
     private Properties properties;
 
+    private static void loadTenantRegistry(int tenantId) throws RegistryException {
+        TenantRegistryLoader tenantRegistryLoader = AuthenticatorFrameworkDataHolder.getInstance().
+                getTenantRegistryLoader();
+        AuthenticatorFrameworkDataHolder.getInstance().getTenantIndexingLoader().loadTenantIndex(tenantId);
+        tenantRegistryLoader.loadTenantRegistry(tenantId);
+    }
+
     @Override
     public void init() {
 
@@ -73,10 +80,7 @@ public class JWTAuthenticator implements WebappAuthenticator {
     @Override
     public boolean canHandle(Request request) {
         String authorizationHeader = request.getHeader(JWTAuthenticator.JWT_ASSERTION_HEADER);
-        if ((authorizationHeader != null) && !authorizationHeader.isEmpty()) {
+        return (authorizationHeader != null) && !authorizationHeader.isEmpty();
-            return true;
-        }
-        return false;
     }
 
     @Override
@@ -106,7 +110,7 @@ public class JWTAuthenticator implements WebappAuthenticator {
             if (publicKey == null) {
                 loadTenantRegistry(tenantId);
                 KeyStoreManager keyStoreManager = KeyStoreManager.getInstance(tenantId);
-                if (tenantDomain.equals(MultitenantConstants.SUPER_TENANT_DOMAIN_NAME)) {
+                if (MultitenantConstants.SUPER_TENANT_DOMAIN_NAME.equals(tenantDomain)) {
                     String defaultPublicKey = properties.getProperty("DefaultPublicKey");
                     if (defaultPublicKey != null && !defaultPublicKey.isEmpty()) {
                         boolean isDefaultPublicKey = Boolean.parseBoolean(defaultPublicKey);
@@ -182,13 +186,13 @@ public class JWTAuthenticator implements WebappAuthenticator {
     }
 
     @Override
-    public void setProperties(Properties properties) {
+    public Properties getProperties() {
-        this.properties = properties;
+        return properties;
     }
 
     @Override
-    public Properties getProperties() {
+    public void setProperties(Properties properties) {
-        return properties;
+        this.properties = properties;
     }
 
     @Override
@@ -198,11 +202,4 @@ public class JWTAuthenticator implements WebappAuthenticator {
         }
         return this.properties.getProperty(name);
     }
-
-    private static void loadTenantRegistry(int tenantId) throws RegistryException {
-        TenantRegistryLoader tenantRegistryLoader = AuthenticatorFrameworkDataHolder.getInstance().
-                getTenantRegistryLoader();
-        AuthenticatorFrameworkDataHolder.getInstance().getTenantIndexingLoader().loadTenantIndex(tenantId);
-        tenantRegistryLoader.loadTenantRegistry(tenantId);
-    }
 }