Update javaxval/src/test/java/org/baeldung/javaxval/messageinterpolator/ParameterMessageInterpolaterIntegrationTest.java

update to use the givenX_whenY_thenZ naming convention for tests

Co-Authored-By: KevinGilmore <kpg102@gmail.com>

couchbase/src/main/java/com/baeldung/couchbase/async/CouchbaseEntity.java

@@ -0,0 +1,9 @@
+package com.baeldung.couchbase.async;
+
+public interface CouchbaseEntity {
+
+    String getId();
+
+    void setId(String id);
+
+}

couchbase/src/main/java/com/baeldung/couchbase/async/person/Person.java

@@ -0,0 +1,90 @@
+package com.baeldung.couchbase.async.person;
+
+import com.baeldung.couchbase.async.CouchbaseEntity;
+
+public class Person implements CouchbaseEntity {
+
+    private String id;
+    private String type;
+    private String name;
+    private String homeTown;
+
+    Person() {
+    }
+
+    public Person(Builder b) {
+        this.id = b.id;
+        this.type = b.type;
+        this.name = b.name;
+        this.homeTown = b.homeTown;
+    }
+
+    @Override
+    public String getId() {
+        return id;
+    }
+
+    @Override
+    public void setId(String id) {
+        this.id = id;
+    }
+
+    public String getType() {
+        return type;
+    }
+
+    public void setType(String type) {
+        this.type = type;
+    }
+
+    public String getName() {
+        return name;
+    }
+
+    public void setName(String name) {
+        this.name = name;
+    }
+
+    public String getHomeTown() {
+        return homeTown;
+    }
+
+    public void setHomeTown(String homeTown) {
+        this.homeTown = homeTown;
+    }
+
+    public static class Builder {
+        private String id;
+        private String type;
+        private String name;
+        private String homeTown;
+
+        public static Builder newInstance() {
+            return new Builder();
+        }
+
+        public Person build() {
+            return new Person(this);
+        }
+
+        public Builder id(String id) {
+            this.id = id;
+            return this;
+        }
+
+        public Builder type(String type) {
+            this.type = type;
+            return this;
+        }
+
+        public Builder name(String name) {
+            this.name = name;
+            return this;
+        }
+
+        public Builder homeTown(String homeTown) {
+            this.homeTown = homeTown;
+            return this;
+        }
+    }
+}

couchbase/src/main/java/com/baeldung/couchbase/async/person/PersonCrudService.java

@@ -0,0 +1,24 @@
+package com.baeldung.couchbase.async.person;
+
+import javax.annotation.PostConstruct;
+
+import org.springframework.beans.factory.annotation.Autowired;
+import org.springframework.beans.factory.annotation.Qualifier;
+import org.springframework.stereotype.Service;
+
+import com.baeldung.couchbase.async.service.AbstractCrudService;
+import com.baeldung.couchbase.async.service.BucketService;
+
+@Service
+public class PersonCrudService extends AbstractCrudService<Person> {
+
+    @Autowired
+    public PersonCrudService(@Qualifier("TutorialBucketService") BucketService bucketService, PersonDocumentConverter converter) {
+        super(bucketService, converter);
+    }
+
+    @PostConstruct
+    private void init() {
+        loadBucket();
+    }
+}

couchbase/src/main/java/com/baeldung/couchbase/async/person/PersonDocumentConverter.java

@@ -0,0 +1,28 @@
+package com.baeldung.couchbase.async.person;
+
+import org.springframework.stereotype.Service;
+
+import com.baeldung.couchbase.async.service.JsonDocumentConverter;
+import com.couchbase.client.java.document.JsonDocument;
+import com.couchbase.client.java.document.json.JsonObject;
+
+@Service
+public class PersonDocumentConverter implements JsonDocumentConverter<Person> {
+
+    @Override
+    public JsonDocument toDocument(Person p) {
+        JsonObject content = JsonObject.empty().put("type", "Person").put("name", p.getName()).put("homeTown", p.getHomeTown());
+        return JsonDocument.create(p.getId(), content);
+    }
+
+    @Override
+    public Person fromDocument(JsonDocument doc) {
+        JsonObject content = doc.content();
+        Person p = new Person();
+        p.setId(doc.id());
+        p.setType("Person");
+        p.setName(content.getString("name"));
+        p.setHomeTown(content.getString("homeTown"));
+        return p;
+    }
+}

couchbase/src/main/java/com/baeldung/couchbase/async/person/RegistrationService.java

@@ -0,0 +1,28 @@
+package com.baeldung.couchbase.async.person;
+
+import org.springframework.beans.factory.annotation.Autowired;
+import org.springframework.stereotype.Service;
+
+import com.couchbase.client.core.CouchbaseException;
+
+@Service
+public class RegistrationService {
+
+    @Autowired
+    private PersonCrudService crud;
+
+    public void registerNewPerson(String name, String homeTown) {
+        Person person = new Person();
+        person.setName(name);
+        person.setHomeTown(homeTown);
+        crud.create(person);
+    }
+
+    public Person findRegistrant(String id) {
+        try {
+            return crud.read(id);
+        } catch (CouchbaseException e) {
+            return crud.readFromReplica(id);
+        }
+    }
+}

couchbase/src/main/java/com/baeldung/couchbase/async/service/AbstractBucketService.java

@@ -0,0 +1,27 @@
+package com.baeldung.couchbase.async.service;
+
+import com.couchbase.client.java.Bucket;
+
+public abstract class AbstractBucketService implements BucketService {
+
+    private ClusterService clusterService;
+
+    private Bucket bucket;
+
+    protected void openBucket() {
+        bucket = clusterService.openBucket(getBucketName(), getBucketPassword());
+    }
+
+    protected abstract String getBucketName();
+
+    protected abstract String getBucketPassword();
+
+    public AbstractBucketService(ClusterService clusterService) {
+        this.clusterService = clusterService;
+    }
+
+    @Override
+    public Bucket getBucket() {
+        return bucket;
+    }
+}

couchbase/src/main/java/com/baeldung/couchbase/async/service/AbstractCrudService.java

@@ -0,0 +1,142 @@
+package com.baeldung.couchbase.async.service;
+
+import java.util.ArrayList;
+import java.util.List;
+import java.util.UUID;
+import java.util.concurrent.TimeUnit;
+
+import org.slf4j.Logger;
+import org.slf4j.LoggerFactory;
+
+import com.baeldung.couchbase.async.CouchbaseEntity;
+import com.couchbase.client.core.BackpressureException;
+import com.couchbase.client.core.time.Delay;
+import com.couchbase.client.java.AsyncBucket;
+import com.couchbase.client.java.Bucket;
+import com.couchbase.client.java.ReplicaMode;
+import com.couchbase.client.java.document.JsonDocument;
+import com.couchbase.client.java.util.retry.RetryBuilder;
+
+import rx.Observable;
+import rx.functions.Action1;
+import rx.functions.Func1;
+
+public abstract class AbstractCrudService<T extends CouchbaseEntity> implements CrudService<T> {
+
+    private static final Logger logger = LoggerFactory.getLogger(AbstractCrudService.class);
+
+    private BucketService bucketService;
+    private Bucket bucket;
+    private JsonDocumentConverter<T> converter;
+
+    public AbstractCrudService(BucketService bucketService, JsonDocumentConverter<T> converter) {
+        this.bucketService = bucketService;
+        this.converter = converter;
+    }
+
+    protected void loadBucket() {
+        bucket = bucketService.getBucket();
+    }
+
+    @Override
+    public void create(T t) {
+        if (t.getId() == null) {
+            t.setId(UUID.randomUUID().toString());
+        }
+        JsonDocument doc = converter.toDocument(t);
+        bucket.insert(doc);
+    }
+
+    @Override
+    public T read(String id) {
+        JsonDocument doc = bucket.get(id);
+        return (doc == null ? null : converter.fromDocument(doc));
+    }
+
+    @Override
+    public T readFromReplica(String id) {
+        List<JsonDocument> docs = bucket.getFromReplica(id, ReplicaMode.FIRST);
+        return (docs.isEmpty() ? null : converter.fromDocument(docs.get(0)));
+    }
+
+    @Override
+    public void update(T t) {
+        JsonDocument doc = converter.toDocument(t);
+        bucket.upsert(doc);
+    }
+
+    @Override
+    public void delete(String id) {
+        bucket.remove(id);
+    }
+
+    @Override
+    public List<T> readBulk(Iterable<String> ids) {
+        final AsyncBucket asyncBucket = bucket.async();
+        Observable<JsonDocument> asyncOperation = Observable.from(ids).flatMap(new Func1<String, Observable<JsonDocument>>() {
+            public Observable<JsonDocument> call(String key) {
+                return asyncBucket.get(key);
+            }
+        });
+
+        final List<T> items = new ArrayList<T>();
+        try {
+            asyncOperation.toBlocking().forEach(new Action1<JsonDocument>() {
+                public void call(JsonDocument doc) {
+                    T item = converter.fromDocument(doc);
+                    items.add(item);
+                }
+            });
+        } catch (Exception e) {
+            logger.error("Error during bulk get", e);
+        }
+
+        return items;
+    }
+
+    @Override
+    public void createBulk(Iterable<T> items) {
+        final AsyncBucket asyncBucket = bucket.async();
+        Observable.from(items).flatMap(new Func1<T, Observable<JsonDocument>>() {
+            @SuppressWarnings("unchecked")
+            @Override
+            public Observable<JsonDocument> call(final T t) {
+                if (t.getId() == null) {
+                    t.setId(UUID.randomUUID().toString());
+                }
+                JsonDocument doc = converter.toDocument(t);
+                return asyncBucket.insert(doc).retryWhen(RetryBuilder.anyOf(BackpressureException.class).delay(Delay.exponential(TimeUnit.MILLISECONDS, 100)).max(10).build());
+            }
+        }).last().toBlocking().single();
+    }
+
+    @Override
+    public void updateBulk(Iterable<T> items) {
+        final AsyncBucket asyncBucket = bucket.async();
+        Observable.from(items).flatMap(new Func1<T, Observable<JsonDocument>>() {
+            @SuppressWarnings("unchecked")
+            @Override
+            public Observable<JsonDocument> call(final T t) {
+                JsonDocument doc = converter.toDocument(t);
+                return asyncBucket.upsert(doc).retryWhen(RetryBuilder.anyOf(BackpressureException.class).delay(Delay.exponential(TimeUnit.MILLISECONDS, 100)).max(10).build());
+            }
+        }).last().toBlocking().single();
+    }
+
+    @Override
+    public void deleteBulk(Iterable<String> ids) {
+        final AsyncBucket asyncBucket = bucket.async();
+        Observable.from(ids).flatMap(new Func1<String, Observable<JsonDocument>>() {
+            @SuppressWarnings("unchecked")
+            @Override
+            public Observable<JsonDocument> call(String key) {
+                return asyncBucket.remove(key).retryWhen(RetryBuilder.anyOf(BackpressureException.class).delay(Delay.exponential(TimeUnit.MILLISECONDS, 100)).max(10).build());
+            }
+        }).last().toBlocking().single();
+    }
+
+    @Override
+    public boolean exists(String id) {
+        return bucket.exists(id);
+    }
+}

couchbase/src/main/java/com/baeldung/couchbase/async/service/BucketService.java

@@ -0,0 +1,8 @@
+package com.baeldung.couchbase.async.service;
+
+import com.couchbase.client.java.Bucket;
+
+public interface BucketService {
+
+    Bucket getBucket();
+}

couchbase/src/main/java/com/baeldung/couchbase/async/service/ClusterService.java

@@ -0,0 +1,8 @@
+package com.baeldung.couchbase.async.service;
+
+import com.couchbase.client.java.Bucket;
+
+public interface ClusterService {
+
+    Bucket openBucket(String name, String password);
+}

couchbase/src/main/java/com/baeldung/couchbase/async/service/ClusterServiceImpl.java

@@ -0,0 +1,42 @@
+package com.baeldung.couchbase.async.service;
+
+import java.util.Map;
+import java.util.concurrent.ConcurrentHashMap;
+
+import javax.annotation.PostConstruct;
+
+import org.springframework.beans.factory.annotation.Autowired;
+import org.springframework.stereotype.Service;
+
+import com.couchbase.client.java.Bucket;
+import com.couchbase.client.java.Cluster;
+import com.couchbase.client.java.CouchbaseCluster;
+import com.couchbase.client.java.env.CouchbaseEnvironment;
+import com.couchbase.client.java.env.DefaultCouchbaseEnvironment;
+
+@Service
+public class ClusterServiceImpl implements ClusterService {
+
+    private Cluster cluster;
+    private Map<String, Bucket> buckets = new ConcurrentHashMap<>();
+    
+    @Autowired
+    public ClusterServiceImpl(Cluster cluster) {
+        this.cluster = cluster;
+    }
+
+    @PostConstruct
+    private void init() {
+        CouchbaseEnvironment env = DefaultCouchbaseEnvironment.create();
+        cluster = CouchbaseCluster.create(env, "localhost");
+    }
+
+    @Override
+    synchronized public Bucket openBucket(String name, String password) {
+        if (!buckets.containsKey(name)) {
+            Bucket bucket = cluster.openBucket(name, password);
+            buckets.put(name, bucket);
+        }
+        return buckets.get(name);
+    }
+}

couchbase/src/main/java/com/baeldung/couchbase/async/service/CrudService.java

@@ -0,0 +1,26 @@
+package com.baeldung.couchbase.async.service;
+
+import java.util.List;
+
+public interface CrudService<T> {
+
+    void create(T t);
+
+    T read(String id);
+
+    T readFromReplica(String id);
+
+    void update(T t);
+
+    void delete(String id);
+
+    List<T> readBulk(Iterable<String> ids);
+
+    void createBulk(Iterable<T> items);
+
+    void updateBulk(Iterable<T> items);
+
+    void deleteBulk(Iterable<String> ids);
+
+    boolean exists(String id);
+}

couchbase/src/main/java/com/baeldung/couchbase/async/service/JsonDocumentConverter.java

@@ -0,0 +1,10 @@
+package com.baeldung.couchbase.async.service;
+
+import com.couchbase.client.java.document.JsonDocument;
+
+public interface JsonDocumentConverter<T> {
+
+    JsonDocument toDocument(T t);
+
+    T fromDocument(JsonDocument doc);
+}

couchbase/src/main/java/com/baeldung/couchbase/async/service/TutorialBucketService.java

@@ -0,0 +1,33 @@
+package com.baeldung.couchbase.async.service;
+
+import javax.annotation.PostConstruct;
+
+import org.springframework.beans.factory.annotation.Autowired;
+import org.springframework.beans.factory.annotation.Qualifier;
+import org.springframework.stereotype.Service;
+
+@Service
+@Qualifier("TutorialBucketService")
+public class TutorialBucketService extends AbstractBucketService {
+
+    @PostConstruct
+    void init() {
+        openBucket();
+    }
+
+    @Autowired
+    public TutorialBucketService(ClusterService clusterService) {
+        super(clusterService);
+        openBucket();
+    }
+
+    @Override
+    protected String getBucketName() {
+        return "baeldung-tutorial";
+    }
+
+    @Override
+    protected String getBucketPassword() {
+        return "";
+    }
+}

couchbase/src/main/java/com/baeldung/couchbase/intro/CodeSnippets.java

@@ -0,0 +1,87 @@
+package com.baeldung.couchbase.intro;
+
+import java.util.List;
+import java.util.UUID;
+
+import com.couchbase.client.core.CouchbaseException;
+import com.couchbase.client.java.Bucket;
+import com.couchbase.client.java.Cluster;
+import com.couchbase.client.java.CouchbaseCluster;
+import com.couchbase.client.java.ReplicaMode;
+import com.couchbase.client.java.document.JsonDocument;
+import com.couchbase.client.java.document.json.JsonObject;
+import com.couchbase.client.java.env.CouchbaseEnvironment;
+import com.couchbase.client.java.env.DefaultCouchbaseEnvironment;
+
+public class CodeSnippets {
+
+    static Cluster loadClusterWithDefaultEnvironment() {
+        return CouchbaseCluster.create("localhost");
+    }
+
+    static Cluster loadClusterWithCustomEnvironment() {
+        CouchbaseEnvironment env = DefaultCouchbaseEnvironment.builder().connectTimeout(10000).kvTimeout(3000).build();
+        return CouchbaseCluster.create(env, "localhost");
+    }
+
+    static Bucket loadDefaultBucketWithBlankPassword(Cluster cluster) {
+        return cluster.openBucket();
+    }
+
+    static Bucket loadBaeldungBucket(Cluster cluster) {
+        return cluster.openBucket("baeldung", "");
+    }
+
+    static JsonDocument insertExample(Bucket bucket) {
+        JsonObject content = JsonObject.empty().put("name", "John Doe").put("type", "Person").put("email", "john.doe@mydomain.com").put("homeTown", "Chicago");
+        String id = UUID.randomUUID().toString();
+        JsonDocument document = JsonDocument.create(id, content);
+        JsonDocument inserted = bucket.insert(document);
+        return inserted;
+    }
+
+    static JsonDocument retrieveAndUpsertExample(Bucket bucket, String id) {
+        JsonDocument document = bucket.get(id);
+        JsonObject content = document.content();
+        content.put("homeTown", "Kansas City");
+        JsonDocument upserted = bucket.upsert(document);
+        return upserted;
+    }
+
+    static JsonDocument replaceExample(Bucket bucket, String id) {
+        JsonDocument document = bucket.get(id);
+        JsonObject content = document.content();
+        content.put("homeTown", "Milwaukee");
+        JsonDocument replaced = bucket.replace(document);
+        return replaced;
+    }
+
+    static JsonDocument removeExample(Bucket bucket, String id) {
+        JsonDocument removed = bucket.remove(id);
+        return removed;
+    }
+
+    static JsonDocument getFirstFromReplicaExample(Bucket bucket, String id) {
+        try {
+            return bucket.get(id);
+        } catch (CouchbaseException e) {
+            List<JsonDocument> list = bucket.getFromReplica(id, ReplicaMode.FIRST);
+            if (!list.isEmpty()) {
+                return list.get(0);
+            }
+        }
+        return null;
+    }
+
+    static JsonDocument getLatestReplicaVersion(Bucket bucket, String id) {
+        long maxCasValue = -1;
+        JsonDocument latest = null;
+        for (JsonDocument replica : bucket.getFromReplica(id, ReplicaMode.ALL)) {
+            if (replica.cas() > maxCasValue) {
+                latest = replica;
+                maxCasValue = replica.cas();
+            }
+        }
+        return latest;
+    }
+}

couchbase/src/main/java/com/baeldung/couchbase/mapreduce/CouchbaseKeyGenerator.java

@@ -0,0 +1,6 @@
+package com.baeldung.couchbase.mapreduce;
+
+public interface CouchbaseKeyGenerator<T> {
+
+    String generateKey(T t);
+}

couchbase/src/main/java/com/baeldung/couchbase/mapreduce/DuplicateKeyException.java

@@ -0,0 +1,10 @@
+package com.baeldung.couchbase.mapreduce;
+
+@SuppressWarnings("serial")
+public class DuplicateKeyException extends Exception {
+
+    public DuplicateKeyException(String s) {
+        super(s);
+    }
+
+}

couchbase/src/main/java/com/baeldung/couchbase/mapreduce/RandomUUIDGenerator.java

@@ -0,0 +1,11 @@
+package com.baeldung.couchbase.mapreduce;
+
+import java.util.UUID;
+
+public class RandomUUIDGenerator<T> implements CouchbaseKeyGenerator<T> {
+
+    @Override
+    public String generateKey(T t) {
+        return UUID.randomUUID().toString();
+    }
+}

couchbase/src/main/java/com/baeldung/couchbase/mapreduce/StudentGrade.java

@@ -0,0 +1,50 @@
+package com.baeldung.couchbase.mapreduce;
+
+public class StudentGrade {
+
+    private String name;
+    private String course;
+    private Integer grade;
+    private Integer hours;
+    
+    public StudentGrade() { }
+    
+    public StudentGrade(String name, String course, Integer grade, Integer hours) {
+        this.name = name;
+        this.course = course;
+        this.grade = grade;
+        this.hours = hours;
+    }
+    
+    public String getName() {
+        return name;
+    }
+    
+    public void setName(String name) {
+        this.name = name;
+    }
+    
+    public String getCourse() {
+        return course;
+    }
+    
+    public void setCourse(String course) {
+        this.course = course;
+    }
+    
+    public Integer getGrade() {
+        return grade;
+    }
+    
+    public void setGrade(Integer grade) {
+        this.grade = grade;
+    }
+
+    public Integer getHours() {
+        return hours;
+    }
+
+    public void setHours(Integer hours) {
+        this.hours = hours;
+    }
+}

couchbase/src/main/java/com/baeldung/couchbase/mapreduce/StudentGradeKeyGenerator.java

@@ -0,0 +1,9 @@
+package com.baeldung.couchbase.mapreduce;
+
+public class StudentGradeKeyGenerator implements CouchbaseKeyGenerator<StudentGrade> {
+
+    @Override
+    public String generateKey(StudentGrade g) {
+        return g.getName() + ":" + g.getCourse();
+    }
+}

couchbase/src/main/java/com/baeldung/couchbase/mapreduce/StudentGradeQueryBuilder.java

@@ -0,0 +1,70 @@
+package com.baeldung.couchbase.mapreduce;
+
+import com.couchbase.client.deps.com.fasterxml.jackson.databind.ObjectMapper;
+import com.couchbase.client.java.document.json.JsonArray;
+import com.couchbase.client.java.view.ViewQuery;
+
+public class StudentGradeQueryBuilder {
+
+    final ObjectMapper om = new ObjectMapper();
+    
+    public ViewQuery findAll() {
+        return ViewQuery.from("studentGrades", "findByCourse");
+    }
+    
+    public ViewQuery findByCourse(String course) {
+        return ViewQuery.from("studentGrades", "findByCourse")
+                .key(course);
+    }
+    
+    public ViewQuery findByCourses(String... courses) {
+        return ViewQuery.from("studentGrades", "findByCourse")
+                .keys(JsonArray.from(courses));
+    }
+    
+    public ViewQuery findByGradeInRange(int lower, int upper, boolean inclusiveEnd) {
+        return ViewQuery.from("studentGrades", "findByGrade")
+                .startKey(lower)
+                .endKey(upper)
+                .inclusiveEnd(inclusiveEnd);
+    }
+    
+    public ViewQuery findByGradeLessThan(int upper) {
+        return ViewQuery.from("studentGrades", "findByGrade")
+                .endKey(upper)
+                .inclusiveEnd(false);
+    }
+    
+    public ViewQuery findByGradeGreaterThan(int lower) {
+        return ViewQuery.from("studentGrades", "findByGrade")
+                .startKey(lower);
+    }
+        
+    public ViewQuery findByCourseAndGradeInRange(String course, int minGrade, int maxGrade, boolean inclusiveEnd) {
+        return ViewQuery.from("studentGrades", "findByCourseAndGrade")
+                .startKey(JsonArray.from(course, minGrade))
+                .endKey(JsonArray.from(course, maxGrade))
+                .inclusiveEnd(inclusiveEnd);
+    }
+    
+    public ViewQuery findTopGradesByCourse(String course, int limit) {
+        return ViewQuery.from("studentGrades", "findByCourseAndGrade")
+                .startKey(JsonArray.from(course, 100))
+                .endKey(JsonArray.from(course, 0))
+                .inclusiveEnd(true)
+                .descending()
+                .limit(limit);
+    }
+    
+    public ViewQuery countStudentsByCourse() {
+        return ViewQuery.from("studentGrades", "countStudentsByCourse")
+                .reduce()
+                .groupLevel(1);
+    }
+    
+    public ViewQuery sumCreditsByStudent() {
+        return ViewQuery.from("studentGrades", "sumCreditsByStudent")
+                .reduce()
+                .groupLevel(1);
+    }
+}

couchbase/src/main/java/com/baeldung/couchbase/mapreduce/StudentGradeService.java

@@ -0,0 +1,169 @@
+package com.baeldung.couchbase.mapreduce;
+
+import java.util.ArrayList;
+import java.util.HashMap;
+import java.util.List;
+import java.util.Map;
+import java.util.Map.Entry;
+
+import com.couchbase.client.deps.com.fasterxml.jackson.databind.ObjectMapper;
+import com.couchbase.client.java.Bucket;
+import com.couchbase.client.java.CouchbaseCluster;
+import com.couchbase.client.java.document.JsonDocument;
+import com.couchbase.client.java.document.json.JsonArray;
+import com.couchbase.client.java.document.json.JsonObject;
+import com.couchbase.client.java.view.ViewQuery;
+import com.couchbase.client.java.view.ViewResult;
+import com.couchbase.client.java.view.ViewRow;
+
+public class StudentGradeService {
+
+    final CouchbaseKeyGenerator<StudentGrade> keyGenerator;
+    final CouchbaseCluster cluster;
+    final Bucket bucket;
+    final ObjectMapper om = new ObjectMapper();
+    final StudentGradeQueryBuilder queryBuilder;
+    
+    public StudentGradeService(CouchbaseKeyGenerator<StudentGrade> keyGenerator) {
+        this.keyGenerator = keyGenerator;
+        this.queryBuilder = new StudentGradeQueryBuilder();
+        cluster = CouchbaseCluster.create("127.0.0.1");
+        bucket = cluster.openBucket("baeldung-tutorial");
+    }
+    
+    public String insert(StudentGrade studentGrade) throws DuplicateKeyException {
+        String id = keyGenerator.generateKey(studentGrade);
+        if(bucket.exists(id)) {
+            throw new DuplicateKeyException("document already exists with key " + id);
+        }
+        JsonObject content = JsonObject.empty()
+                .put("type", "StudentGrade")
+                .put("name", studentGrade.getName())
+                .put("course", studentGrade.getCourse())
+                .put("grade", studentGrade.getGrade())
+                .put("hours", studentGrade.getHours());
+        JsonDocument doc = JsonDocument.create(id, content);
+        bucket.insert(doc);
+        return id;
+    }
+    
+    public List<JsonDocument> findAll() {
+        ViewQuery query = queryBuilder.findAll();
+        ViewResult result = bucket.query(query);
+        return extractDocuments(result);
+    }
+    
+    private List<JsonDocument> extractDocuments(ViewResult result) {
+        List<JsonDocument> docs = new ArrayList<>();
+        for(ViewRow row : result.allRows()) {
+            JsonDocument doc = row.document();
+            docs.add(doc);
+        }
+        return docs;
+    }
+    
+    public List<JsonDocument> findByCourse(String course) {
+        ViewQuery query = queryBuilder.findByCourse(course);
+        ViewResult result = bucket.query(query);
+        return extractDocuments(result);
+    }
+    
+    public List<JsonDocument> findByCourses(String... courses) {
+        ViewQuery query = queryBuilder.findByCourses(courses);
+        ViewResult result = bucket.query(query);
+        return extractDocuments(result);
+    }
+    
+    public List<JsonDocument> findByGradeInRange(int lower, int upper, boolean inclusiveEnd) {
+        ViewQuery query = queryBuilder.findByGradeInRange(lower, upper, inclusiveEnd);
+        ViewResult result = bucket.query(query);
+        return extractDocuments(result);
+    }
+    
+    public List<JsonDocument> findByGradeLessThan(int upper) {
+        ViewQuery query = queryBuilder.findByGradeLessThan(upper);
+        ViewResult result = bucket.query(query);
+        return extractDocuments(result);
+    }
+    
+    public List<JsonDocument> findByGradeGreaterThan(int lower) {
+        ViewQuery query = queryBuilder.findByGradeGreaterThan(lower);
+        ViewResult result = bucket.query(query);
+        return extractDocuments(result);
+    }
+        
+    public List<JsonDocument> findByCourseAndGradeInRange(String course, int minGrade, int maxGrade, boolean inclusiveEnd) {
+        ViewQuery query = queryBuilder.findByCourseAndGradeInRange(course, minGrade, maxGrade, inclusiveEnd);
+        ViewResult result = bucket.query(query);
+        return extractDocuments(result);
+    }
+    
+    public List<JsonDocument> findTopGradesByCourse(String course, int limit) {
+        ViewQuery query = queryBuilder.findTopGradesByCourse(course, limit);
+        ViewResult result = bucket.query(query);
+        return extractDocuments(result);
+    }
+    
+    public Map<String, Long> countStudentsByCourse() {
+        ViewQuery query = ViewQuery.from("studentGrades", "countStudentsByCourse")
+                .reduce()
+                .groupLevel(1);
+        ViewResult result = bucket.query(query);
+        
+        Map<String, Long> numStudentsByCourse = new HashMap<>();
+        for(ViewRow row : result.allRows()) {
+            JsonArray keyArray = (JsonArray) row.key();
+            String course = keyArray.getString(0);
+            long count = Long.valueOf(row.value().toString());
+            numStudentsByCourse.put(course, count);
+        }
+        
+        return numStudentsByCourse;
+    }
+    
+    public Map<String, Long> sumCreditHoursByStudent() {
+        ViewQuery query = ViewQuery.from("studentGrades", "sumHoursByStudent")
+                .reduce()
+                .groupLevel(1);
+        ViewResult result = bucket.query(query);
+        
+        Map<String, Long> creditHoursByStudent = new HashMap<>();
+        for(ViewRow row : result.allRows()) {
+            String course = (String) row.key();
+            long sum = Long.valueOf(row.value().toString());
+            creditHoursByStudent.put(course, sum);
+        }
+        
+        return creditHoursByStudent;
+    }
+    
+    public Map<String, Long> sumGradePointsByStudent() {
+        ViewQuery query = ViewQuery.from("studentGrades", "sumGradePointsByStudent")
+                .reduce()
+                .groupLevel(1);
+        ViewResult result = bucket.query(query);
+        
+        Map<String, Long> gradePointsByStudent = new HashMap<>();
+        for(ViewRow row : result.allRows()) {
+            String course = (String) row.key();
+            long sum = Long.valueOf(row.value().toString());
+            gradePointsByStudent.put(course, sum);
+        }
+        
+        return gradePointsByStudent;
+    }
+    
+    public Map<String, Float> calculateGpaByStudent() {
+        Map<String, Long> creditHoursByStudent = sumCreditHoursByStudent();
+        Map<String, Long> gradePointsByStudent = sumGradePointsByStudent();
+        
+        Map<String, Float> result = new HashMap<>();
+        for(Entry<String, Long> creditHoursEntry : creditHoursByStudent.entrySet()) {
+            String name = creditHoursEntry.getKey();
+            long totalHours = creditHoursEntry.getValue();
+            long totalGradePoints = gradePointsByStudent.get(name);
+            result.put(name, ((float) totalGradePoints / totalHours));
+        }
+        return result;
+    }
+}

couchbase/src/main/java/com/baeldung/couchbase/n1ql/BucketFactory.java

@@ -0,0 +1,26 @@
+package com.baeldung.couchbase.n1ql;
+
+import com.couchbase.client.java.Bucket;
+import com.couchbase.client.java.Cluster;
+import org.springframework.beans.factory.annotation.Autowired;
+import org.springframework.stereotype.Service;
+
+@Service
+public class BucketFactory {
+
+    @Autowired
+    private Cluster cluster;
+
+    private Bucket travelSampleBucket;
+    private Bucket testBucket;
+
+    public Bucket getTravelSampleBucket() {
+        return (travelSampleBucket != null) ?
+                travelSampleBucket : cluster.openBucket("travel-sample");
+    }
+
+    public Bucket getTestBucket() {
+        return (testBucket != null) ?
+                testBucket : cluster.openBucket("test");
+    }
+}

couchbase/src/main/java/com/baeldung/couchbase/n1ql/CodeSnippets.java

@@ -0,0 +1,34 @@
+package com.baeldung.couchbase.n1ql;
+
+import com.couchbase.client.java.query.N1qlQueryResult;
+import com.fasterxml.jackson.databind.JsonNode;
+import com.fasterxml.jackson.databind.ObjectMapper;
+
+import java.io.IOException;
+import java.util.List;
+import java.util.Objects;
+import java.util.logging.Level;
+import java.util.logging.Logger;
+import java.util.stream.Collectors;
+
+public class CodeSnippets {
+
+    private static ObjectMapper objectMapper = new ObjectMapper();
+
+    private static final Logger logger = Logger.getLogger(CodeSnippets.class.getName());
+
+    public static List<JsonNode> extractJsonResult(N1qlQueryResult result) {
+      return result.allRows().stream()
+        .map(row -> {
+            try {
+              return objectMapper.readTree(row.value().toString());
+            }catch (IOException e) {
+               logger.log(Level.WARNING, e.getLocalizedMessage());
+               return null;
+            }
+        })
+        .filter(Objects::nonNull)
+        .collect(Collectors.toList());
+    }
+
+}

couchbase/src/main/java/com/baeldung/couchbase/spring/person/Person.java

@@ -0,0 +1,86 @@
+package com.baeldung.couchbase.spring.person;
+
+public class Person {
+
+    private String id;
+    private String type;
+    private String name;
+    private String homeTown;
+
+    Person() {
+    }
+
+    public Person(Builder b) {
+        this.id = b.id;
+        this.type = b.type;
+        this.name = b.name;
+        this.homeTown = b.homeTown;
+    }
+
+    public String getId() {
+        return id;
+    }
+
+    public void setId(String id) {
+        this.id = id;
+    }
+
+    public String getType() {
+        return type;
+    }
+
+    public void setType(String type) {
+        this.type = type;
+    }
+
+    public String getName() {
+        return name;
+    }
+
+    public void setName(String name) {
+        this.name = name;
+    }
+
+    public String getHomeTown() {
+        return homeTown;
+    }
+
+    public void setHomeTown(String homeTown) {
+        this.homeTown = homeTown;
+    }
+
+    public static class Builder {
+        private String id;
+        private String type;
+        private String name;
+        private String homeTown;
+
+        public static Builder newInstance() {
+            return new Builder();
+        }
+
+        public Person build() {
+            return new Person(this);
+        }
+
+        public Builder id(String id) {
+            this.id = id;
+            return this;
+        }
+
+        public Builder type(String type) {
+            this.type = type;
+            return this;
+        }
+
+        public Builder name(String name) {
+            this.name = name;
+            return this;
+        }
+
+        public Builder homeTown(String homeTown) {
+            this.homeTown = homeTown;
+            return this;
+        }
+    }
+}

couchbase/src/main/java/com/baeldung/couchbase/spring/person/PersonCrudService.java

@@ -0,0 +1,69 @@
+package com.baeldung.couchbase.spring.person;
+
+import java.util.List;
+import java.util.UUID;
+
+import javax.annotation.PostConstruct;
+
+import org.springframework.beans.factory.annotation.Autowired;
+import org.springframework.stereotype.Service;
+
+import com.baeldung.couchbase.spring.service.CrudService;
+import com.baeldung.couchbase.spring.service.TutorialBucketService;
+import com.couchbase.client.java.Bucket;
+import com.couchbase.client.java.ReplicaMode;
+import com.couchbase.client.java.document.JsonDocument;
+
+@Service
+public class PersonCrudService implements CrudService<Person> {
+
+    @Autowired
+    private TutorialBucketService bucketService;
+
+    @Autowired
+    private PersonDocumentConverter converter;
+
+    private Bucket bucket;
+
+    @PostConstruct
+    private void init() {
+        bucket = bucketService.getBucket();
+    }
+
+    @Override
+    public void create(Person person) {
+        if (person.getId() == null) {
+            person.setId(UUID.randomUUID().toString());
+        }
+        JsonDocument document = converter.toDocument(person);
+        bucket.insert(document);
+    }
+
+    @Override
+    public Person read(String id) {
+        JsonDocument doc = bucket.get(id);
+        return (doc != null ? converter.fromDocument(doc) : null);
+    }
+
+    @Override
+    public Person readFromReplica(String id) {
+        List<JsonDocument> docs = bucket.getFromReplica(id, ReplicaMode.FIRST);
+        return (docs.isEmpty() ? null : converter.fromDocument(docs.get(0)));
+    }
+
+    @Override
+    public void update(Person person) {
+        JsonDocument document = converter.toDocument(person);
+        bucket.upsert(document);
+    }
+
+    @Override
+    public void delete(String id) {
+        bucket.remove(id);
+    }
+
+    @Override
+    public boolean exists(String id) {
+        return bucket.exists(id);
+    }
+}

couchbase/src/main/java/com/baeldung/couchbase/spring/person/PersonDocumentConverter.java

@@ -0,0 +1,28 @@
+package com.baeldung.couchbase.spring.person;
+
+import org.springframework.stereotype.Service;
+
+import com.baeldung.couchbase.spring.service.JsonDocumentConverter;
+import com.couchbase.client.java.document.JsonDocument;
+import com.couchbase.client.java.document.json.JsonObject;
+
+@Service
+public class PersonDocumentConverter implements JsonDocumentConverter<Person> {
+
+    @Override
+    public JsonDocument toDocument(Person p) {
+        JsonObject content = JsonObject.empty().put("type", "Person").put("name", p.getName()).put("homeTown", p.getHomeTown());
+        return JsonDocument.create(p.getId(), content);
+    }
+
+    @Override
+    public Person fromDocument(JsonDocument doc) {
+        JsonObject content = doc.content();
+        Person p = new Person();
+        p.setId(doc.id());
+        p.setType("Person");
+        p.setName(content.getString("name"));
+        p.setHomeTown(content.getString("homeTown"));
+        return p;
+    }
+}

couchbase/src/main/java/com/baeldung/couchbase/spring/person/RegistrationService.java

@@ -0,0 +1,28 @@
+package com.baeldung.couchbase.spring.person;
+
+import org.springframework.beans.factory.annotation.Autowired;
+import org.springframework.stereotype.Service;
+
+import com.couchbase.client.core.CouchbaseException;
+
+@Service
+public class RegistrationService {
+
+    @Autowired
+    private PersonCrudService crud;
+
+    public void registerNewPerson(String name, String homeTown) {
+        Person person = new Person();
+        person.setName(name);
+        person.setHomeTown(homeTown);
+        crud.create(person);
+    }
+
+    public Person findRegistrant(String id) {
+        try {
+            return crud.read(id);
+        } catch (CouchbaseException e) {
+            return crud.readFromReplica(id);
+        }
+    }
+}

couchbase/src/main/java/com/baeldung/couchbase/spring/service/BucketService.java

@@ -0,0 +1,9 @@
+package com.baeldung.couchbase.spring.service;
+
+import com.couchbase.client.java.Bucket;
+
+public interface BucketService {
+
+    Bucket getBucket();
+
+}

couchbase/src/main/java/com/baeldung/couchbase/spring/service/ClusterService.java

@@ -0,0 +1,17 @@
+package com.baeldung.couchbase.spring.service;
+
+import java.util.List;
+
+import com.couchbase.client.java.AsyncBucket;
+import com.couchbase.client.java.Bucket;
+import com.couchbase.client.java.document.JsonDocument;
+
+public interface ClusterService {
+
+    Bucket openBucket(String name, String password);
+
+    List<JsonDocument> getDocuments(Bucket bucket, Iterable<String> keys);
+
+    List<JsonDocument> getDocumentsAsync(AsyncBucket bucket, Iterable<String> keys);
+
+}

couchbase/src/main/java/com/baeldung/couchbase/spring/service/ClusterServiceImpl.java

@@ -0,0 +1,81 @@
+package com.baeldung.couchbase.spring.service;
+
+import java.util.ArrayList;
+import java.util.List;
+import java.util.Map;
+import java.util.concurrent.ConcurrentHashMap;
+
+import javax.annotation.PostConstruct;
+
+import org.slf4j.Logger;
+import org.slf4j.LoggerFactory;
+import org.springframework.stereotype.Service;
+
+import com.couchbase.client.java.AsyncBucket;
+import com.couchbase.client.java.Bucket;
+import com.couchbase.client.java.Cluster;
+import com.couchbase.client.java.CouchbaseCluster;
+import com.couchbase.client.java.document.JsonDocument;
+import com.couchbase.client.java.env.CouchbaseEnvironment;
+import com.couchbase.client.java.env.DefaultCouchbaseEnvironment;
+
+import rx.Observable;
+import rx.functions.Action1;
+import rx.functions.Func1;
+
+@Service
+public class ClusterServiceImpl implements ClusterService {
+    private static final Logger logger = LoggerFactory.getLogger(ClusterServiceImpl.class);
+
+    private Cluster cluster;
+    private Map<String, Bucket> buckets = new ConcurrentHashMap<>();
+
+    @PostConstruct
+    private void init() {
+        CouchbaseEnvironment env = DefaultCouchbaseEnvironment.create();
+        cluster = CouchbaseCluster.create(env, "localhost");
+    }
+
+    @Override
+    synchronized public Bucket openBucket(String name, String password) {
+        if (!buckets.containsKey(name)) {
+            Bucket bucket = cluster.openBucket(name, password);
+            buckets.put(name, bucket);
+        }
+        return buckets.get(name);
+    }
+
+    @Override
+    public List<JsonDocument> getDocuments(Bucket bucket, Iterable<String> keys) {
+        List<JsonDocument> docs = new ArrayList<>();
+        for (String key : keys) {
+            JsonDocument doc = bucket.get(key);
+            if (doc != null) {
+                docs.add(doc);
+            }
+        }
+        return docs;
+    }
+
+    @Override
+    public List<JsonDocument> getDocumentsAsync(final AsyncBucket asyncBucket, Iterable<String> keys) {
+        Observable<JsonDocument> asyncBulkGet = Observable.from(keys).flatMap(new Func1<String, Observable<JsonDocument>>() {
+            public Observable<JsonDocument> call(String key) {
+                return asyncBucket.get(key);
+            }
+        });
+
+        final List<JsonDocument> docs = new ArrayList<>();
+        try {
+            asyncBulkGet.toBlocking().forEach(new Action1<JsonDocument>() {
+                public void call(JsonDocument doc) {
+                    docs.add(doc);
+                }
+            });
+        } catch (Exception e) {
+            logger.error("Error during bulk get", e);
+        }
+
+        return docs;
+    }
+}

couchbase/src/main/java/com/baeldung/couchbase/spring/service/CrudService.java

@@ -0,0 +1,16 @@
+package com.baeldung.couchbase.spring.service;
+
+public interface CrudService<T> {
+
+    void create(T t);
+
+    T read(String id);
+
+    T readFromReplica(String id);
+
+    void update(T t);
+
+    void delete(String id);
+
+    boolean exists(String id);
+}

couchbase/src/main/java/com/baeldung/couchbase/spring/service/JsonDocumentConverter.java

@@ -0,0 +1,10 @@
+package com.baeldung.couchbase.spring.service;
+
+import com.couchbase.client.java.document.JsonDocument;
+
+public interface JsonDocumentConverter<T> {
+
+    JsonDocument toDocument(T t);
+
+    T fromDocument(JsonDocument doc);
+}

couchbase/src/main/java/com/baeldung/couchbase/spring/service/TutorialBucketService.java

@@ -0,0 +1,29 @@
+package com.baeldung.couchbase.spring.service;
+
+import javax.annotation.PostConstruct;
+
+import org.springframework.beans.factory.annotation.Autowired;
+import org.springframework.beans.factory.annotation.Qualifier;
+import org.springframework.stereotype.Service;
+
+import com.couchbase.client.java.Bucket;
+
+@Service
+@Qualifier("TutorialBucketService")
+public class TutorialBucketService implements BucketService {
+
+    @Autowired
+    private ClusterService couchbase;
+
+    private Bucket bucket;
+
+    @PostConstruct
+    private void init() {
+        bucket = couchbase.openBucket("baeldung-tutorial", "");
+    }
+
+    @Override
+    public Bucket getBucket() {
+        return bucket;
+    }
+}

couchbase/src/main/resources/logback.xml

@@ -0,0 +1,19 @@
+<?xml version="1.0" encoding="UTF-8"?>
+<configuration>
+    <appender name="STDOUT" class="ch.qos.logback.core.ConsoleAppender">
+        <encoder>
+            <pattern>%d{HH:mm:ss.SSS} [%thread] %-5level %logger{36} - %msg%n
+            </pattern>
+        </encoder>
+    </appender>
+
+    <logger name="org.springframework" level="WARN" />
+    <logger name="org.springframework.transaction" level="WARN" />
+
+    <!-- in order to debug some marshalling issues, this needs to be TRACE -->
+    <logger name="org.springframework.web.servlet.mvc" level="WARN" />
+
+    <root level="INFO">
+        <appender-ref ref="STDOUT" />
+    </root>
+</configuration>