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package com.zoo;
import com.datastax.driver.core.Cluster;
import com.datastax.driver.core.Host;
import com.datastax.driver.core.Metadata;
import com.datastax.driver.core.ResultSet;
import com.datastax.driver.core.Row;
import com.datastax.driver.core.Session;
/**
*
* @author yankai913@gmail.com
* @date 2015-9-25
*
*/
public class SimpleClient {
private Cluster cluster;
private Session session;
public Session getSession() {
return this.session;
}
/**
* 连接集群，创建执行cql的session对象。
*
* @param node
*/
public void connect(String node) {
cluster = Cluster.builder().addContactPoint(node).build();
Metadata metadata = cluster.getMetadata();
System.out.printf("Connected to cluster: %s\n", metadata.getClusterName());
for (Host host : metadata.getAllHosts()) {
System.out.printf("Datacenter: %s; Host: %s; Rack: %s\n", host.getDatacenter(),
host.getAddress(), host.getRack());
}
session = cluster.connect();
System.out.println();
}
/**
* 创建schema， 创建库：simplex，表：simplex.songs，表：simplex.playlists
*/
public void createSchema() {
session.execute("CREATE KEYSPACE IF NOT EXISTS simplex WITH replication "
+ "= {'class':'SimpleStrategy', 'replication_factor':3};");
session.execute("CREATE TABLE IF NOT EXISTS simplex.songs (" + "id uuid PRIMARY KEY," + "title text,"
+ "album text," + "artist text," + "tags set<text>," + "data blob" + ");");
session.execute("CREATE TABLE IF NOT EXISTS simplex.playlists (" + "id uuid," + "title text,"
+ "album text, " + "artist text," + "song_id uuid,"
+ "PRIMARY KEY (id, title, album, artist)" + ");");
}
/**
* 插入数据
*/
public void loadData() {
session.execute("INSERT INTO simplex.songs (id, title, album, artist, tags) " + "VALUES ("
+ "756716f7-2e54-4715-9f00-91dcbea6cf50," + "'La Petite Tonkinoise',"
+ "'Bye Bye Blackbird'," + "'Joséphine Baker'," + "{'jazz', '2013'})" + ";");
session.execute("INSERT INTO simplex.playlists (id, song_id, title, album,artist) " + "VALUES ("
+ "2cc9ccb7-6221-4ccb-8387-f22b6a1b354d," + "756716f7-2e54-4715-9f00-91dcbea6cf50,"
+ "'La Petite Tonkinoise'," + "'Bye Bye Blackbird'," + "'Joséphine Baker'" + ");");
}
/**
* 查询simplex.songs
*/
public void querySchema() {
ResultSet results2 =
session.execute("SELECT * FROM simplex.songs "
+ "WHERE id = 756716f7-2e54-4715-9f00-91dcbea6cf50;");
for (Row row : results2) {
System.out.println(row.getUUID("id") + "\t" + row.getString("title") + "\t"
+ row.getString("album") + "\t" + row.getString("artist") + "\t"
+ row.getSet("tags", String.class));
}
System.out.println();
}
/**
* 修改simplex.songs
*/
public void updateSchema() {
session.execute("UPDATE simplex.songs set title = 'La Petite Tonkinoise Updated'"
+ " WHERE id = 756716f7-2e54-4715-9f00-91dcbea6cf50;");
}
/**
* 删除simplex.songs
*/
public void deleteSchema() {
session.execute("DELETE FROM simplex.songs " + " WHERE id = 756716f7-2e54-4715-9f00-91dcbea6cf50;");
}
/**
* 删除keyspace，keyspace可以理解成oracle里的schema
*/
public void dropSchema() {
session.execute("DROP KEYSPACE simplex;");
}
public void close() {
session.close();
cluster.close();
}
public static void main(String[] args) {
SimpleClient client = new SimpleClient();
try {
client.connect("127.0.0.1");
client.dropSchema();
client.createSchema();
client.loadData();
System.out.println("before update...");
client.querySchema();
System.out.println("after update...");
client.updateSchema();
client.querySchema();
System.out.println();
client.deleteSchema();
System.out.println("after delete...");
client.querySchema();
System.out.println();
}
catch (Throwable t) {
t.printStackTrace();
}
finally {
client.close();
}
}
}
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