Make constants final classes instead of interfaces

This commit prohibits implementation of the empty interface and
instantiation of the class.  Refer to _Effective Java_ item 19 for
more background.

apis/cloudsigma/src/main/java/org/jclouds/cloudsigma/reference/CloudSigmaConstants.java

@@ -20,11 +20,14 @@ package org.jclouds.cloudsigma.reference;
  *
  * @author Adrian Cole
  */
-public class CloudSigmaConstants {
+public final class CloudSigmaConstants {
 
     /**
      * default VNC password used on new machines
      */
     public static final String PROPERTY_VNC_PASSWORD = "jclouds.cloudsigma.vnc-password";
-    
+
+    private CloudSigmaConstants() {
+        throw new AssertionError("intentionally unimplemented");
+    }
 }

apis/cloudwatch/src/main/java/org/jclouds/cloudwatch/domain/AutoScalingConstants.java

@@ -23,7 +23,7 @@ package org.jclouds.cloudwatch.domain;
  *
  * @author Jeremy Whitlock
  */
-public interface AutoScalingConstants {
+public final class AutoScalingConstants {
 
    public static class Dimension {
 
@@ -43,4 +43,7 @@ public interface AutoScalingConstants {
 
    }
 
+   private AutoScalingConstants() {
+      throw new AssertionError("intentionally unimplemented");
+   }
 }

apis/cloudwatch/src/main/java/org/jclouds/cloudwatch/domain/DynamoDBConstants.java

@@ -23,7 +23,7 @@ package org.jclouds.cloudwatch.domain;
  *
  * @author Jeremy Whitlock
  */
-public interface DynamoDBConstants {
+public final class DynamoDBConstants {
 
    public static class Dimension {
 
@@ -44,4 +44,7 @@ public interface DynamoDBConstants {
 
    }
 
+   private DynamoDBConstants() {
+      throw new AssertionError("intentionally unimplemented");
+   }
 }

apis/cloudwatch/src/main/java/org/jclouds/cloudwatch/domain/EBSConstants.java

@@ -23,7 +23,7 @@ package org.jclouds.cloudwatch.domain;
  *
  * @author Jeremy Whitlock
  */
-public interface EBSConstants {
+public final class EBSConstants {
 
    public static class Dimension {
 
@@ -44,4 +44,7 @@ public interface EBSConstants {
 
    }
 
+   private EBSConstants() {
+      throw new AssertionError("intentionally unimplemented");
+   }
 }

apis/cloudwatch/src/main/java/org/jclouds/cloudwatch/domain/EC2Constants.java

@@ -23,7 +23,7 @@ package org.jclouds.cloudwatch.domain;
  *
  * @author Jeremy Whitlock
  */
-public interface EC2Constants {
+public final class EC2Constants {
 
    public static class Dimension {
 
@@ -46,4 +46,7 @@ public interface EC2Constants {
 
    }
 
+   private EC2Constants() {
+      throw new AssertionError("intentionally unimplemented");
+   }
 }

apis/cloudwatch/src/main/java/org/jclouds/cloudwatch/domain/ELBConstants.java

@@ -23,7 +23,7 @@ package org.jclouds.cloudwatch.domain;
  *
  * @author Jeremy Whitlock
  */
-public interface ELBConstants {
+public final class ELBConstants {
 
    public static class Dimension {
 
@@ -47,4 +47,7 @@ public interface ELBConstants {
 
    }
 
+   private ELBConstants() {
+      throw new AssertionError("intentionally unimplemented");
+   }
 }

apis/cloudwatch/src/main/java/org/jclouds/cloudwatch/domain/EMRConstants.java

@@ -23,7 +23,7 @@ package org.jclouds.cloudwatch.domain;
  *
  * @author Jeremy Whitlock
  */
-public interface EMRConstants {
+public final class EMRConstants {
 
    public static class Dimension {
 
@@ -60,4 +60,7 @@ public interface EMRConstants {
 
    }
 
+   private EMRConstants() {
+      throw new AssertionError("intentionally unimplemented");
+   }
 }

apis/cloudwatch/src/main/java/org/jclouds/cloudwatch/domain/RDSConstants.java

@@ -23,7 +23,7 @@ package org.jclouds.cloudwatch.domain;
  *
  * @author Jeremy Whitlock
  */
-public interface RDSConstants {
+public final class RDSConstants {
 
    public static class Dimension {
 
@@ -51,4 +51,7 @@ public interface RDSConstants {
 
    }
 
+   private RDSConstants() {
+      throw new AssertionError("intentionally unimplemented");
+   }
 }

apis/cloudwatch/src/main/java/org/jclouds/cloudwatch/domain/SNSConstants.java

@@ -23,7 +23,7 @@ package org.jclouds.cloudwatch.domain;
  *
  * @author Jeremy Whitlock
  */
-public interface SNSConstants {
+public final class SNSConstants {
 
    public static class Dimension {
 
@@ -40,4 +40,7 @@ public interface SNSConstants {
 
    }
 
+   private SNSConstants() {
+      throw new AssertionError("intentionally unimplemented");
+   }
 }

apis/cloudwatch/src/main/java/org/jclouds/cloudwatch/domain/SQSConstants.java

@@ -23,7 +23,7 @@ package org.jclouds.cloudwatch.domain;
  *
  * @author Jeremy Whitlock
  */
-public interface SQSConstants {
+public final class SQSConstants {
 
    public static class Dimension {
 
@@ -44,4 +44,7 @@ public interface SQSConstants {
 
    }
 
+   private SQSConstants() {
+      throw new AssertionError("intentionally unimplemented");
+   }
 }

apis/cloudwatch/src/main/java/org/jclouds/cloudwatch/domain/StorageGatewayConstants.java

@@ -23,7 +23,7 @@ package org.jclouds.cloudwatch.domain;
  *
  * @author Jeremy Whitlock
  */
-public interface StorageGatewayConstants {
+public final class StorageGatewayConstants {
 
    public static class Dimension {
 
@@ -52,4 +52,7 @@ public interface StorageGatewayConstants {
 
    }
 
+   private StorageGatewayConstants() {
+      throw new AssertionError("intentionally unimplemented");
+   }
 }

apis/ec2/src/main/java/org/jclouds/ec2/reference/EC2Constants.java

@@ -22,7 +22,7 @@ package org.jclouds.ec2.reference;
  * 
  * @author Adrian Cole
  */
-public interface EC2Constants {
+public class EC2Constants {
    /**
     * Listing the universe of amis is extremely expensive. set this to a comma separated value of
     * the ami owners you wish to use in {@link ComputeService}
@@ -46,4 +46,7 @@ public interface EC2Constants {
     */
    public static final String PROPERTY_EC2_GENERATE_INSTANCE_NAMES = "jclouds.ec2.generate-instance-names";
 
+   protected EC2Constants() {
+      throw new AssertionError("intentionally unimplemented");
+   }
 }

apis/elasticstack/src/main/java/org/jclouds/elasticstack/reference/ElasticStackConstants.java

@@ -21,11 +21,14 @@ package org.jclouds.elasticstack.reference;
  *
  * @author Adrian Cole
  */
-public class ElasticStackConstants {
+public final class ElasticStackConstants {
 
     /**
      * default VNC password used on new machines
      */
     public static final String PROPERTY_VNC_PASSWORD = "jclouds.elasticstack.vnc-password";
-    
+
+    private ElasticStackConstants() {
+        throw new AssertionError("intentionally unimplemented");
+    }
 }

apis/filesystem/src/main/java/org/jclouds/filesystem/reference/FilesystemConstants.java

@@ -21,9 +21,12 @@ package org.jclouds.filesystem.reference;
  *
  * @author Alfredo "Rainbowbreeze" Morresi
  */
-public class FilesystemConstants {
+public final class FilesystemConstants {
 
     /** Specify the base directory where provider starts its file operations - must exists */
     public static final String PROPERTY_BASEDIR = "jclouds.filesystem.basedir";
-    
+
+    private FilesystemConstants() {
+        throw new AssertionError("intentionally unimplemented");
+    }
 }

apis/s3/src/main/java/org/jclouds/s3/reference/S3Constants.java

@@ -21,7 +21,7 @@ package org.jclouds.s3.reference;
  * 
  * @author Adrian Cole
  */
-public interface S3Constants {
+public final class S3Constants {
 
    /**
     * S3 service's XML Namespace, as used in XML request and response documents.
@@ -34,4 +34,7 @@ public interface S3Constants {
    public static final String PROPERTY_S3_SERVICE_PATH = "jclouds.s3.service-path";
    public static final String PROPERTY_S3_VIRTUAL_HOST_BUCKETS = "jclouds.s3.virtual-host-buckets";
 
+   private S3Constants() {
+      throw new AssertionError("intentionally unimplemented");
+   }
 }

apis/sts/src/main/java/org/jclouds/aws/reference/AWSConstants.java

@@ -21,8 +21,12 @@ package org.jclouds.aws.reference;
  * 
  * @author Adrian Cole
  */
-public interface AWSConstants {
+public final class AWSConstants {
    public static final String PROPERTY_ZONECLIENT_ENDPOINT = "jclouds.aws.zoneclient-endpoint";
    public static final String PROPERTY_AUTH_TAG = "jclouds.aws.auth.tag";
    public static final String PROPERTY_HEADER_TAG = "jclouds.aws.header.tag";
+
+   private AWSConstants() {
+      throw new AssertionError("intentionally unimplemented");
+   }
 }

apis/swift/src/main/java/org/jclouds/openstack/swift/reference/SwiftConstants.java

@@ -22,23 +22,26 @@ package org.jclouds.openstack.swift.reference;
  * 
  * @author Adrian Cole
  */
-public interface SwiftConstants {
+public final class SwiftConstants {
    /**
     * For an integer value N, limits the number of results to at most N values.
     */
-   String LIMIT = "limit";
+   public static final String LIMIT = "limit";
    /**
     * Given a string value X, return Object names greater in value than the specified marker.
     */
-   String MARKER = "marker";
+   public static final String MARKER = "marker";
    /**
     * For a string value X, causes the results to be limited to Object names beginning with the
     * substring X.
     */
-   String PREFIX = "prefix";
+   public static final String PREFIX = "prefix";
    /**
     * For a string value X, return the Object names nested in the pseudo path.
     */
-   String PATH = "path";
+   public static final String PATH = "path";
 
+   private SwiftConstants() {
+      throw new AssertionError("intentionally unimplemented");
+   }
 }

apis/vcloud/src/main/java/org/jclouds/vcloud/reference/VCloudConstants.java

@@ -21,7 +21,7 @@ package org.jclouds.vcloud.reference;
  * 
  * @author Adrian Cole
  */
-public interface VCloudConstants {
+public final class VCloudConstants {
    public static final String PROPERTY_VCLOUD_VERSION_SCHEMA = "jclouds.vcloud.version.schema";
    /**
     * name of the default org that your vApp will join, if an org isn't
@@ -48,4 +48,7 @@ public interface VCloudConstants {
 
    public static final String PROPERTY_VCLOUD_TIMEOUT_TASK_COMPLETED = "jclouds.vcloud.timeout.task-complete";
 
+   private VCloudConstants() {
+      throw new AssertionError("intentionally unimplemented");
+   }
 }

blobstore/src/main/java/org/jclouds/blobstore/reference/BlobStoreConstants.java

@@ -25,7 +25,7 @@ import com.google.common.collect.ImmutableList;
  * 
  * @author Adrian Cole
  */
-public interface BlobStoreConstants {
+public final class BlobStoreConstants {
    /**
     * <p/>
     * To interoperate with other S3 tools, we also accept the following:
@@ -57,4 +57,7 @@ public interface BlobStoreConstants {
 
    public static final String BLOBSTORE_LOGGER = "jclouds.blobstore";
 
+   private BlobStoreConstants() {
+      throw new AssertionError("intentionally unimplemented");
+   }
 }

compute/src/main/java/org/jclouds/compute/reference/ComputeServiceConstants.java

@@ -43,7 +43,7 @@ import com.google.inject.Inject;
  * 
  * @author Adrian Cole
  */
-public interface ComputeServiceConstants {
+public final class ComputeServiceConstants {
 
    public static final String COMPUTE_LOGGER = "jclouds.compute";
    public static final String LOCAL_PARTITION_GB_PATTERN = "disk_drive/%s/gb";
@@ -131,4 +131,8 @@ public interface ComputeServiceConstants {
       @Named(TIMEOUT_IMAGE_AVAILABLE)
       public long imageAvailable = TimeUnit.MINUTES.toMillis(45);
    }
+
+   private ComputeServiceConstants() {
+      throw new AssertionError("intentionally unimplemented");
+   }
 }

core/src/main/java/org/jclouds/Constants.java

@@ -24,7 +24,7 @@ import org.jclouds.location.reference.LocationConstants;
  * 
  * @author Adrian Cole
  */
-public interface Constants {
+public final class Constants {
    /**
     * Integer property. default (0)
     * <p/>
@@ -304,4 +304,8 @@ public interface Constants {
     * The maximum number of blob deletes happening in parallel at any point in time.
     */
    public static final String PROPERTY_MAX_PARALLEL_DELETES = "jclouds.max-parallel-deletes";
+
+   private Constants() {
+      throw new AssertionError("intentionally unimplemented");
+   }
 }

core/src/main/java/org/jclouds/location/reference/LocationConstants.java

@@ -20,11 +20,15 @@ package org.jclouds.location.reference;
  * 
  * @author Adrian Cole
  */
-public interface LocationConstants {
+public final class LocationConstants {
    public static final String ENDPOINT = "endpoint";
    public static final String ISO3166_CODES = "iso3166-codes";
    public static final String PROPERTY_REGIONS = "jclouds.regions";
    public static final String PROPERTY_REGION = "jclouds.region";
    public static final String PROPERTY_ZONES = "jclouds.zones";
    public static final String PROPERTY_ZONE = "jclouds.zone";
+
+   private LocationConstants() {
+      throw new AssertionError("intentionally unimplemented");
+   }
 }

loadbalancer/src/main/java/org/jclouds/loadbalancer/reference/LoadBalancerConstants.java

@@ -20,8 +20,11 @@ package org.jclouds.loadbalancer.reference;
  * 
  * @author Adrian Cole
  */
-public interface LoadBalancerConstants {
+public final class LoadBalancerConstants {
 
    public static final String LOADBALANCER_LOGGER = "jclouds.loadbalancer";
 
+   private LoadBalancerConstants() {
+      throw new AssertionError("intentionally unimplemented");
+   }
 }

providers/aws-ec2/src/main/java/org/jclouds/aws/ec2/reference/AWSEC2Constants.java

@@ -23,7 +23,7 @@ import org.jclouds.ec2.reference.EC2Constants;
  * 
  * @author Adrian Cole
  */
-public interface AWSEC2Constants extends EC2Constants {
+public final class AWSEC2Constants extends EC2Constants {
    /**
     * expression to find amis that work on the cluster instance type <br/>
     * ex. {@code
@@ -36,4 +36,7 @@ public interface AWSEC2Constants extends EC2Constants {
    public static final String PROPERTY_EC2_CC_REGIONS = "jclouds.ec2.cc-regions";
    public static final String PROPERTY_EC2_AMI_QUERY = "jclouds.ec2.ami-query";
 
+   private AWSEC2Constants() {
+      throw new AssertionError("intentionally unimplemented");
+   }
 }

providers/glesys/src/main/java/org/jclouds/glesys/reference/GleSYSConstants.java

@@ -28,7 +28,7 @@ import org.jclouds.compute.domain.ComputeMetadata;
  * 
  * @author Adam Lowe
  */
-public class GleSYSConstants {
+public final class GleSYSConstants {
 
    public static final Pattern JCLOUDS_ID_TO_PLATFORM = Pattern.compile("([a-zA-Z]+) .*");
    
@@ -40,4 +40,8 @@ public class GleSYSConstants {
       }
       return matcher.group(1);
    }
+
+   private GleSYSConstants() {
+      throw new AssertionError("intentionally unimplemented");
+   }
 }

providers/hpcloud-objectstorage/src/main/java/org/jclouds/hpcloud/objectstorage/reference/HPCloudObjectStorageConstants.java

@@ -22,9 +22,13 @@ package org.jclouds.hpcloud.objectstorage.reference;
  * 
  * @author Jeremy Daggett
  */
-public interface HPCloudObjectStorageConstants {
+public final class HPCloudObjectStorageConstants {
    /**
     * The CDN Endpoint property
     */
    public static final String PROPERTY_CDN_ENDPOINT = "jclouds.hpcloud-objectstorage.cdn.endpoint";
+
+   private HPCloudObjectStorageConstants() {
+      throw new AssertionError("intentionally unimplemented");
+   }
 }

providers/softlayer/src/main/java/org/jclouds/softlayer/reference/SoftLayerConstants.java

@@ -21,7 +21,7 @@ package org.jclouds.softlayer.reference;
  * 
  * @author Adrian Cole
  */
-public interface SoftLayerConstants {
+public final class SoftLayerConstants {
 
    /**
     * Name of the product package corresponding to cloud servers
@@ -53,4 +53,7 @@ public interface SoftLayerConstants {
     */
    public static final String PROPERTY_SOFTLAYER_VIRTUALGUEST_PRICES = "jclouds.softlayer.virtualguest.prices";
 
+   private SoftLayerConstants() {
+      throw new AssertionError("intentionally unimplemented");
+   }
 }