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Merge branch 'master' of https://github.com/annasp/tutorials into annasp-master

This commit is contained in:
Zeger Hendrikse 2016-08-28 23:45:33 +02:00
parent b4e0135927 13b91a9b04
commit 4bf338680a
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96
java-cassandra/pom.xml Normal file
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<project xmlns="http://maven.apache.org/POM/4.0.0" xmlns:xsi="http://www.w3.org/2001/XMLSchema-instance" xsi:schemaLocation="http://maven.apache.org/POM/4.0.0 http://maven.apache.org/xsd/maven-4.0.0.xsd">
<modelVersion>4.0.0</modelVersion>
<groupId>com.baeldung</groupId>
<artifactId>cassandra-java-client</artifactId>
<version>1.0.0-SNAPSHOT</version>
<name>cassandra-java-client</name>
<properties>
<project.build.sourceEncoding>UTF-8</project.build.sourceEncoding>
<!-- logging -->
<org.slf4j.version>1.7.21</org.slf4j.version>
<logback.version>1.1.7</logback.version>
<!-- testing -->
<org.hamcrest.version>1.3</org.hamcrest.version>
<junit.version>4.12</junit.version>
<mockito.version>1.10.19</mockito.version>
<testng.version>6.8</testng.version>
<assertj.version>3.5.1</assertj.version>
<!-- maven plugins -->
<maven-compiler-plugin.version>3.5.1</maven-compiler-plugin.version>
<!-- Cassandra -->
<cassandra-driver-core.version>3.0.3</cassandra-driver-core.version>
</properties>
<dependencies>
<!-- Cassandra -->
<dependency>
<groupId>com.datastax.cassandra</groupId>
<artifactId>cassandra-driver-core</artifactId>
<version>${cassandra-driver-core.version}</version>
<optional>true</optional>
</dependency>
<!-- https://mvnrepository.com/artifact/org.cassandraunit/cassandra-unit -->
<dependency>
<groupId>org.cassandraunit</groupId>
<artifactId>cassandra-unit</artifactId>
<version>2.2.2.1</version>
</dependency>
<!-- logging -->
<dependency>
<groupId>org.slf4j</groupId>
<artifactId>slf4j-api</artifactId>
<version>${org.slf4j.version}</version>
</dependency>
<dependency>
<groupId>ch.qos.logback</groupId>
<artifactId>logback-classic</artifactId>
<version>${logback.version}</version>
<!-- <scope>runtime</scope> -->
</dependency>
<dependency>
<groupId>org.slf4j</groupId>
<artifactId>jcl-over-slf4j</artifactId>
<version>${org.slf4j.version}</version>
<!-- <scope>runtime</scope> --> <!-- some spring dependencies need to compile against jcl -->
</dependency>
<dependency> <!-- needed to bridge to slf4j for projects that use the log4j APIs directly -->
<groupId>org.slf4j</groupId>
<artifactId>log4j-over-slf4j</artifactId>
<version>${org.slf4j.version}</version>
</dependency>
<dependency>
<groupId>junit</groupId>
<artifactId>junit</artifactId>
<version>${junit.version}</version>
<scope>test</scope>
</dependency>
</dependencies>
<build>
<finalName>java-cassandra</finalName>
<plugins>
<plugin>
<groupId>org.apache.maven.plugins</groupId>
<artifactId>maven-compiler-plugin</artifactId>
<version>${maven-compiler-plugin.version}</version>
<configuration>
<source>1.8</source>
<target>1.8</target>
</configuration>
</plugin>
</plugins>
</build>
</project>

44
java-cassandra/src/main/java/com/baeldung/cassandra/java/client/CassandraClient.java Normal file
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package com.baeldung.cassandra.java.client;
import org.slf4j.Logger;
import org.slf4j.LoggerFactory;
import com.baeldung.cassandra.java.client.domain.Book;
import com.baeldung.cassandra.java.client.repository.BookRepository;
import com.baeldung.cassandra.java.client.repository.KeyspaceRepository;
import com.datastax.driver.core.Session;
import com.datastax.driver.core.utils.UUIDs;
public class CassandraClient {
private static final Logger LOG = LoggerFactory.getLogger(CassandraClient.class);
public static void main(String args[]) {
CassandraConnector connector = new CassandraConnector();
connector.connect("127.0.0.1", null);
Session session = connector.getSession();
KeyspaceRepository sr = new KeyspaceRepository(session);
sr.createKeyspace("library", "SimpleStrategy", 1);
sr.useKeyspace("library");
BookRepository br = new BookRepository(session);
br.createTable();
br.alterTablebooks("publisher", "text");
br.createTableBooksByTitle();
Book book = new Book(UUIDs.timeBased(), "Effective Java", "Joshua Bloch", "Programming");
br.insertBookBatch(book);
br.selectAll().forEach(o -> LOG.info("Title in books: " + o.getTitle()));
br.selectAllBookByTitle().forEach(o -> LOG.info("Title in booksByTitle: " + o.getTitle()));
br.deletebookByTitle("Effective Java");
br.deleteTable("books");
br.deleteTable("booksByTitle");
sr.deleteKeyspace("library");
connector.close();
}
}

51
java-cassandra/src/main/java/com/baeldung/cassandra/java/client/CassandraConnector.java Normal file
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package com.baeldung.cassandra.java.client;
import org.slf4j.Logger;
import org.slf4j.LoggerFactory;
import com.datastax.driver.core.Cluster;
import com.datastax.driver.core.Cluster.Builder;
import com.datastax.driver.core.Host;
import com.datastax.driver.core.Metadata;
import com.datastax.driver.core.Session;
/**
*
* This is an implementation of a simple Java client.
*
*/
public class CassandraConnector {
private static final Logger LOG = LoggerFactory.getLogger(CassandraConnector.class);
private Cluster cluster;
private Session session;
public void connect(final String node, final Integer port) {
Builder b = Cluster.builder().addContactPoint(node);
if (port != null) {
b.withPort(port);
}
cluster = b.build();
Metadata metadata = cluster.getMetadata();
LOG.info("Cluster name: " + metadata.getClusterName());
for (Host host : metadata.getAllHosts()) {
LOG.info("Datacenter: " + host.getDatacenter() + " Host: " + host.getAddress() + " Rack: " + host.getRack());
}
session = cluster.connect();
}
public Session getSession() {
return this.session;
}
public void close() {
session.close();
cluster.close();
}
}

67
java-cassandra/src/main/java/com/baeldung/cassandra/java/client/domain/Book.java Normal file
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package com.baeldung.cassandra.java.client.domain;
import java.util.UUID;
public class Book {
private UUID id;
private String title;
private String author;
private String subject;
private String publisher;
public Book() {
}
public Book(UUID id, String title, String author, String subject) {
this.id = id;
this.title = title;
this.author = author;
this.subject = subject;
}
public UUID getId() {
return id;
}
public void setId(UUID id) {
this.id = id;
}
public String getTitle() {
return title;
}
public void setTitle(String title) {
this.title = title;
}
public String getAuthor() {
return author;
}
public void setAuthor(String author) {
this.author = author;
}
public String getSubject() {
return subject;
}
public void setSubject(String subject) {
this.subject = subject;
}
public String getPublisher() {
return publisher;
}
public void setPublisher(String publisher) {
this.publisher = publisher;
}
}

177
java-cassandra/src/main/java/com/baeldung/cassandra/java/client/repository/BookRepository.java Normal file
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package com.baeldung.cassandra.java.client.repository;
import java.util.ArrayList;
import java.util.List;
import com.baeldung.cassandra.java.client.domain.Book;
import com.datastax.driver.core.ResultSet;
import com.datastax.driver.core.Row;
import com.datastax.driver.core.Session;
public class BookRepository {
private static final String TABLE_NAME = "books";
private static final String TABLE_NAME_BY_TITLE = TABLE_NAME + "ByTitle";
private Session session;
public BookRepository(Session session) {
this.session = session;
}
/**
* Creates the books table.
*/
public void createTable() {
StringBuilder sb = new StringBuilder("CREATE TABLE IF NOT EXISTS ").append(TABLE_NAME).append("(").append("id uuid PRIMARY KEY, ").append("title text,").append("author text,").append("subject text);");
final String query = sb.toString();
session.execute(query);
}
/**
* Creates the books table.
*/
public void createTableBooksByTitle() {
StringBuilder sb = new StringBuilder("CREATE TABLE IF NOT EXISTS ").append(TABLE_NAME_BY_TITLE).append("(").append("id uuid, ").append("title text,").append("PRIMARY KEY (title, id));");
final String query = sb.toString();
session.execute(query);
}
/**
* Alters the table books and adds an extra column.
*/
public void alterTablebooks(String columnName, String columnType) {
StringBuilder sb = new StringBuilder("ALTER TABLE ").append(TABLE_NAME).append(" ADD ").append(columnName).append(" ").append(columnType).append(";");
final String query = sb.toString();
session.execute(query);
}
/**
* Insert a row in the table books.
*
* @param book
*/
public void insertbook(Book book) {
StringBuilder sb = new StringBuilder("INSERT INTO ").append(TABLE_NAME).append("(id, title, author, subject) ").append("VALUES (").append(book.getId()).append(", '").append(book.getTitle()).append("', '").append(book.getAuthor()).append("', '")
.append(book.getSubject()).append("');");
final String query = sb.toString();
session.execute(query);
}
/**
* Insert a row in the table booksByTitle.
* @param book
*/
public void insertbookByTitle(Book book) {
StringBuilder sb = new StringBuilder("INSERT INTO ").append(TABLE_NAME_BY_TITLE).append("(id, title) ").append("VALUES (").append(book.getId()).append(", '").append(book.getTitle()).append("');");
final String query = sb.toString();
session.execute(query);
}
/**
* Insert a book into two identical tables using a batch query.
*
* @param book
*/
public void insertBookBatch(Book book) {
StringBuilder sb = new StringBuilder("BEGIN BATCH ")
.append("INSERT INTO ").append(TABLE_NAME).append("(id, title, author, subject) ")
.append("VALUES (").append(book.getId()).append(", '").append(book.getTitle()).append("', '").append(book.getAuthor()).append("', '")
.append(book.getSubject()).append("');")
.append("INSERT INTO ").append(TABLE_NAME_BY_TITLE).append("(id, title) ")
.append("VALUES (").append(book.getId()).append(", '").append(book.getTitle()).append("');")
.append("APPLY BATCH;");
final String query = sb.toString();
session.execute(query);
}
/**
* Select book by id.
*
* @return
*/
public Book selectByTitle(String title) {
StringBuilder sb = new StringBuilder("SELECT * FROM ").append(TABLE_NAME_BY_TITLE).append(" WHERE title = '").append(title).append("';");
final String query = sb.toString();
ResultSet rs = session.execute(query);
List<Book> books = new ArrayList<Book>();
for (Row r : rs) {
Book s = new Book(r.getUUID("id"), r.getString("title"), null, null);
books.add(s);
}
return books.get(0);
}
/**
* Select all books from books
*
* @return
*/
public List<Book> selectAll() {
StringBuilder sb = new StringBuilder("SELECT * FROM ").append(TABLE_NAME);
final String query = sb.toString();
ResultSet rs = session.execute(query);
List<Book> books = new ArrayList<Book>();
for (Row r : rs) {
Book book = new Book(r.getUUID("id"), r.getString("title"), r.getString("author"), r.getString("subject"));
books.add(book);
}
return books;
}
/**
* Select all books from booksByTitle
* @return
*/
public List<Book> selectAllBookByTitle() {
StringBuilder sb = new StringBuilder("SELECT * FROM ").append(TABLE_NAME_BY_TITLE);
final String query = sb.toString();
ResultSet rs = session.execute(query);
List<Book> books = new ArrayList<Book>();
for (Row r : rs) {
Book book = new Book(r.getUUID("id"), r.getString("title"), null, null);
books.add(book);
}
return books;
}
/**
* Delete a book by title.
*/
public void deletebookByTitle(String title) {
StringBuilder sb = new StringBuilder("DELETE FROM ").append(TABLE_NAME_BY_TITLE).append(" WHERE title = '").append(title).append("';");
final String query = sb.toString();
session.execute(query);
}
/**
* Delete table.
*
* @param tableName the name of the table to delete.
*/
public void deleteTable(String tableName) {
StringBuilder sb = new StringBuilder("DROP TABLE IF EXISTS ").append(tableName);
final String query = sb.toString();
session.execute(query);
}
}

54
java-cassandra/src/main/java/com/baeldung/cassandra/java/client/repository/KeyspaceRepository.java Normal file
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package com.baeldung.cassandra.java.client.repository;
import org.slf4j.Logger;
import org.slf4j.LoggerFactory;
import com.datastax.driver.core.Session;
/**
* Repository to handle the Cassandra schema.
*
*/
public class KeyspaceRepository {
private static final Logger LOG = LoggerFactory.getLogger(KeyspaceRepository.class);
private Session session;
public KeyspaceRepository(Session session) {
this.session = session;
}
/**
* Method used to create any keyspace - schema.
*
* @param schemaName the name of the schema.
* @param replicatioonStrategy the replication strategy.
* @param numberOfReplicas the number of replicas.
*
*/
public void createKeyspace(String keyspaceName, String replicatioonStrategy, int numberOfReplicas) {
StringBuilder sb = new StringBuilder("CREATE KEYSPACE IF NOT EXISTS ").append(keyspaceName).append(" WITH replication = {").append("'class':'").append(replicatioonStrategy).append("','replication_factor':").append(numberOfReplicas).append("};");
final String query = sb.toString();
session.execute(query);
}
public void useKeyspace(String keyspace) {
session.execute("USE " + keyspace);
}
/**
* Method used to delete the specified schema.
* It results in the immediate, irreversable removal of the keyspace, including all tables and data contained in the keyspace.
*
* @param schemaName the name of the keyspace to delete.
*/
public void deleteKeyspace(String keyspaceName) {
StringBuilder sb = new StringBuilder("DROP KEYSPACE ").append(keyspaceName);
final String query = sb.toString();
session.execute(query);
}
}

174
java-cassandra/src/test/java/com/baeldung/cassandra/java/client/repository/BookRepositoryIntegrationTest.java Normal file
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package com.baeldung.cassandra.java.client.repository;
import static org.junit.Assert.assertFalse;
import static org.junit.Assert.assertTrue;
import static org.junit.Assert.assertEquals;
import java.io.IOException;
import java.util.List;
import java.util.stream.Collectors;
import org.apache.cassandra.exceptions.ConfigurationException;
import org.apache.thrift.transport.TTransportException;
import org.cassandraunit.utils.EmbeddedCassandraServerHelper;
import org.junit.AfterClass;
import org.junit.Before;
import org.junit.BeforeClass;
import org.junit.Test;
import com.baeldung.cassandra.java.client.CassandraConnector;
import com.baeldung.cassandra.java.client.domain.Book;
import com.datastax.driver.core.ResultSet;
import com.datastax.driver.core.Session;
import com.datastax.driver.core.exceptions.InvalidQueryException;
import com.datastax.driver.core.utils.UUIDs;
public class BookRepositoryIntegrationTest {
private KeyspaceRepository schemaRepository;
private BookRepository bookRepository;
private Session session;
final String KEYSPACE_NAME = "testLibrary";
final String BOOKS = "books";
final String BOOKS_BY_TITLE = "booksByTitle";
@BeforeClass
public static void init() throws ConfigurationException, TTransportException, IOException, InterruptedException {
// Start an embedded Cassandra Server
EmbeddedCassandraServerHelper.startEmbeddedCassandra();
}
@Before
public void connect() {
CassandraConnector client = new CassandraConnector();
client.connect("127.0.0.1", 9142);
this.session = client.getSession();
schemaRepository = new KeyspaceRepository(session);
schemaRepository.createKeyspace(KEYSPACE_NAME, "SimpleStrategy", 1);
schemaRepository.useKeyspace(KEYSPACE_NAME);
bookRepository = new BookRepository(session);
}
@Test
public void whenCreatingATable_thenCreatedCorrectly() {
bookRepository.deleteTable(BOOKS);
bookRepository.createTable();
ResultSet result = session.execute("SELECT * FROM " + KEYSPACE_NAME + "." + BOOKS + ";");
// Collect all the column names in one list.
List<String> columnNames = result.getColumnDefinitions().asList().stream().map(cl -> cl.getName()).collect(Collectors.toList());
assertEquals(columnNames.size(), 4);
assertTrue(columnNames.contains("id"));
assertTrue(columnNames.contains("title"));
assertTrue(columnNames.contains("author"));
assertTrue(columnNames.contains("subject"));
}
@Test
public void whenAlteringTable_thenAddedColumnExists() {
bookRepository.deleteTable(BOOKS);
bookRepository.createTable();
bookRepository.alterTablebooks("publisher", "text");
ResultSet result = session.execute("SELECT * FROM " + KEYSPACE_NAME + "." + BOOKS + ";");
boolean columnExists = result.getColumnDefinitions().asList().stream().anyMatch(cl -> cl.getName().equals("publisher"));
assertTrue(columnExists);
}
@Test
public void whenAddingANewBook_thenBookExists() {
bookRepository.deleteTable(BOOKS_BY_TITLE);
bookRepository.createTableBooksByTitle();
String title = "Effective Java";
String author = "Joshua Bloch";
Book book = new Book(UUIDs.timeBased(), title, author, "Programming");
bookRepository.insertbookByTitle(book);
Book savedBook = bookRepository.selectByTitle(title);
assertEquals(book.getTitle(), savedBook.getTitle());
}
@Test
public void whenAddingANewBookBatch_ThenBookAddedInAllTables() {
// Create table books
bookRepository.deleteTable(BOOKS);
bookRepository.createTable();
// Create table booksByTitle
bookRepository.deleteTable(BOOKS_BY_TITLE);
bookRepository.createTableBooksByTitle();
String title = "Effective Java";
String author = "Joshua Bloch";
Book book = new Book(UUIDs.timeBased(), title, author, "Programming");
bookRepository.insertBookBatch(book);
List<Book> books = bookRepository.selectAll();
assertEquals(1, books.size());
assertTrue(books.stream().anyMatch(b -> b.getTitle().equals("Effective Java")));
List<Book> booksByTitle = bookRepository.selectAllBookByTitle();
assertEquals(1, booksByTitle.size());
assertTrue(booksByTitle.stream().anyMatch(b -> b.getTitle().equals("Effective Java")));
}
@Test
public void whenSelectingAll_thenReturnAllRecords() {
bookRepository.deleteTable(BOOKS);
bookRepository.createTable();
Book book = new Book(UUIDs.timeBased(), "Effective Java", "Joshua Bloch", "Programming");
bookRepository.insertbook(book);
book = new Book(UUIDs.timeBased(), "Clean Code", "Robert C. Martin", "Programming");
bookRepository.insertbook(book);
List<Book> books = bookRepository.selectAll();
assertEquals(2, books.size());
assertTrue(books.stream().anyMatch(b -> b.getTitle().equals("Effective Java")));
assertTrue(books.stream().anyMatch(b -> b.getTitle().equals("Clean Code")));
}
@Test
public void whenDeletingABookByTitle_thenBookIsDeleted() {
bookRepository.deleteTable(BOOKS_BY_TITLE);
bookRepository.createTableBooksByTitle();
Book book = new Book(UUIDs.timeBased(), "Effective Java", "Joshua Bloch", "Programming");
bookRepository.insertbookByTitle(book);
book = new Book(UUIDs.timeBased(), "Clean Code", "Robert C. Martin", "Programming");
bookRepository.insertbookByTitle(book);
bookRepository.deletebookByTitle("Clean Code");
List<Book> books = bookRepository.selectAllBookByTitle();
assertEquals(1, books.size());
assertTrue(books.stream().anyMatch(b -> b.getTitle().equals("Effective Java")));
assertFalse(books.stream().anyMatch(b -> b.getTitle().equals("Clean Code")));
}
@Test(expected = InvalidQueryException.class)
public void whenDeletingATable_thenUnconfiguredTable() {
bookRepository.createTable();
bookRepository.deleteTable(BOOKS);
session.execute("SELECT * FROM " + KEYSPACE_NAME + "." + BOOKS + ";");
}
@AfterClass
public static void cleanup() {
EmbeddedCassandraServerHelper.cleanEmbeddedCassandra();
}
}

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java-cassandra/src/test/java/com/baeldung/cassandra/java/client/repository/KeyspaceRepositoryIntegrationTest.java Normal file
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package com.baeldung.cassandra.java.client.repository;
import static org.junit.Assert.assertFalse;
import static org.junit.Assert.assertTrue;
import static org.junit.Assert.assertEquals;
import java.io.IOException;
import java.util.List;
import java.util.stream.Collectors;
import org.apache.cassandra.exceptions.ConfigurationException;
import org.apache.thrift.transport.TTransportException;
import org.cassandraunit.utils.EmbeddedCassandraServerHelper;
import org.junit.AfterClass;
import org.junit.Before;
import org.junit.BeforeClass;
import org.junit.FixMethodOrder;
import org.junit.Test;
import org.junit.runners.MethodSorters;
import com.baeldung.cassandra.java.client.CassandraConnector;
import com.datastax.driver.core.ResultSet;
import com.datastax.driver.core.Session;
@FixMethodOrder(MethodSorters.NAME_ASCENDING)
public class KeyspaceRepositoryIntegrationTest {
private KeyspaceRepository schemaRepository;
private Session session;
@BeforeClass
public static void init() throws ConfigurationException, TTransportException, IOException, InterruptedException {
// Start an embedded Cassandra Server
EmbeddedCassandraServerHelper.startEmbeddedCassandra();
}
@Before
public void connect() {
CassandraConnector client = new CassandraConnector();
client.connect("127.0.0.1", 9142);
this.session = client.getSession();
schemaRepository = new KeyspaceRepository(session);
}
@Test
public void whenCreatingAKeyspace_thenCreated() {
String keyspaceName = "testBaeldungKeyspace";
schemaRepository.createKeyspace(keyspaceName, "SimpleStrategy", 1);
// ResultSet result = session.execute("SELECT * FROM system_schema.keyspaces WHERE keyspace_name = 'testBaeldungKeyspace';");
ResultSet result = session.execute("SELECT * FROM system.schema_keyspaces;");
// Check if the Keyspace exists in the returned keyspaces.
List<String> matchedKeyspaces = result.all().stream().filter(r -> r.getString(0).equals(keyspaceName.toLowerCase())).map(r -> r.getString(0)).collect(Collectors.toList());
assertEquals(matchedKeyspaces.size(), 1);
assertTrue(matchedKeyspaces.get(0).equals(keyspaceName.toLowerCase()));
}
@Test
public void whenDeletingAKeyspace_thenDoesNotExist() {
String keyspaceName = "testBaeldungKeyspace";
// schemaRepository.createKeyspace(keyspaceName, "SimpleStrategy", 1);
schemaRepository.deleteKeyspace(keyspaceName);
ResultSet result = session.execute("SELECT * FROM system.schema_keyspaces;");
boolean isKeyspaceCreated = result.all().stream().anyMatch(r -> r.getString(0).equals(keyspaceName.toLowerCase()));
assertFalse(isKeyspaceCreated);
}
@AfterClass
public static void cleanup() {
EmbeddedCassandraServerHelper.cleanEmbeddedCassandra();
}
}

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pom.xml
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@ -117,6 +117,7 @@
<module>xstream</module> <module>xstream</module>
<module>dozer</module> <module>dozer</module>
<module>orika</module> <module>orika</module>
<module>java-cassandra</module>
</modules> </modules>
</project> </project>