#2 guava for better filtering

pom.xml

@@ -86,6 +86,10 @@
             <artifactId>aws-java-sdk</artifactId>
             <version>1.6.3</version>
         </dependency>
+        <dependency>
+            <groupId>com.google.guava</groupId>
+            <artifactId>guava</artifactId>
+        </dependency>
         <dependency>
             <groupId>commons-io</groupId>
             <artifactId>commons-io</artifactId>

src/main/java/com/jcabi/s3/AwsBucket.java

@@ -32,6 +32,7 @@
 import com.amazonaws.AmazonServiceException;
 import com.amazonaws.services.s3.AmazonS3;
 import com.amazonaws.services.s3.model.DeleteObjectRequest;
+import com.amazonaws.services.s3.model.ListObjectsRequest;
 import com.amazonaws.services.s3.model.ObjectListing;
 import com.amazonaws.services.s3.model.S3ObjectSummary;
 import com.jcabi.aspects.Immutable;
@@ -101,7 +102,7 @@ public void remove(@NotNull(message = "key can't be NULL")
             aws.deleteObject(new DeleteObjectRequest(this.bkt, key));
             Logger.info(
                 this,
-                "ocket %s removed in bucket %s",
+                "ocket '%s' removed in bucket '%s'",
                 key, this.bkt
             );
         } catch (AmazonServiceException ex) {
@@ -122,14 +123,18 @@ public Iterable<String> list(@NotNull(message = "prefix can't be NULL")
         final String pfx) throws IOException {
         try {
             final AmazonS3 aws = this.regn.aws();
-            final ObjectListing listing = aws.listObjects(this.bkt, pfx);
+            final ObjectListing listing = aws.listObjects(
+                new ListObjectsRequest()
+                    .withBucketName(this.bkt)
+                    .withPrefix(pfx)
+            );
             final Collection<String> list = new LinkedList<String>();
             for (final S3ObjectSummary sum : listing.getObjectSummaries()) {
                 list.add(sum.getKey());
             }
             Logger.info(
                 this,
-                "listed %d ocket(s) with prefix '%s' in bucket %s",
+                "listed %d ocket(s) with prefix '%s' in bucket '%s'",
                 listing.getObjectSummaries().size(), pfx, this.bkt
             );
             return list;

src/main/java/com/jcabi/s3/AwsOcket.java

@@ -101,7 +101,7 @@ public ObjectMetadata meta() throws IOException {
             );
             Logger.info(
                 this,
-                "metadata loaded for ocket %s in bucket %s, etag=%s",
+                "metadata loaded for ocket '%s' in bucket '%s', etag=%s",
                 this.name, this.bkt.name(), meta.getETag()
             );
             return meta;
@@ -123,7 +123,7 @@ public void read(@NotNull(message = "output stream can't be NULL")
             input.close();
             Logger.info(
                 this,
-                "loaded %d byte(s) from ocket %s in bucket %s, etag=%s",
+                "loaded %d byte(s) from ocket '%s' in bucket '%s', etag=%s",
                 bytes, this.name, this.bkt.name(),
                 obj.getObjectMetadata().getETag()
             );
@@ -152,7 +152,7 @@ public void write(
             );
             Logger.info(
                 this,
-                "saved %d byte(s) to ocket %s in bucket %s, etag=%s",
+                "saved %d byte(s) to ocket '%s' in bucket '%s', etag=%s",
                 cnt.getByteCount(), this.name, this.bkt.name(),
                 result.getETag()
             );

src/main/java/com/jcabi/s3/Bucket.java

@@ -29,10 +29,12 @@
  */
 package com.jcabi.s3;
 
+import com.google.common.base.Function;
+import com.google.common.base.Predicate;
+import com.google.common.collect.Iterables;
 import com.jcabi.aspects.Immutable;
 import com.jcabi.aspects.Loggable;
 import java.io.IOException;
-import java.util.Iterator;
 import javax.validation.constraints.NotNull;
 import lombok.EqualsAndHashCode;
 import lombok.ToString;
@@ -132,35 +134,25 @@ public void remove(final String key) throws IOException {
         }
         @Override
         public Iterable<String> list(final String pfx) throws IOException {
-            // @checkstyle AnonInnerLength (50 lines)
-            return new Iterable<String>() {
-                @Override
-                public Iterator<String> iterator() {
-                    final Iterator<String> list;
-                    try {
-                        list = Bucket.Prefixed.this.origin
-                            .list(Bucket.Prefixed.this.extend(pfx)).iterator();
-                    } catch (IOException ex) {
-                        throw new IllegalStateException(ex);
-                    }
-                    return new Iterator<String>() {
-                        @Override
-                        public boolean hasNext() {
-                            return list.hasNext();
-                        }
+            return Iterables.filter(
+                Iterables.transform(
+                    this.origin.list(this.extend(pfx)),
+                    new Function<String, String>() {
                         @Override
-                        public String next() {
-                            return list.next().substring(
+                        public String apply(final String input) {
+                            return input.substring(
                                 Bucket.Prefixed.this.prefix.length()
                             );
                         }
-                        @Override
-                        public void remove() {
-                            list.remove();
-                        }
-                    };
+                    }
+                ),
+                new Predicate<String>() {
+                    @Override
+                    public boolean apply(final String input) {
+                        return !input.isEmpty();
+                    }
                 }
-            };
+            );
         }
         /**
          * Extend name with a prefix.

src/test/java/com/jcabi/s3/AwsBucketITCase.java

@@ -127,17 +127,17 @@ public void listsObjectsInPrefixedBucket() throws Exception {
     public void listsInPrefixedBucketWithouCollisions() throws Exception {
         final Bucket bucket = this.rule.bucket();
         // @checkstyle MultipleStringLiterals (1 line)
-        final String[] names = {"alpha/alpha.xml", "alpha.xml"};
+        final String[] names = {"alpha/", "alpha/beta.xml"};
         for (final String name : names) {
-            new Ocket.Text(bucket.ocket(name)).write("whatsup");
+            new Ocket.Text(bucket.ocket(name)).write("");
         }
         final Bucket bkt = new Bucket.Prefixed(bucket, "alpha/");
         try {
             MatcherAssert.assertThat(
                 bkt.list(""),
                 Matchers.allOf(
                     Matchers.<String>iterableWithSize(1),
-                    Matchers.hasItem("alpha.xml")
+                    Matchers.hasItem("beta.xml")
                 )
             );
         } finally {