项目案例库
案例一：Java 操作 Kudu之创建KuduClient实例
pom.xml
<!-- 指定仓库位置，依次为aliyun、cloudera和jboss仓库 -->
<repositories>
<repository>
<id>aliyun</id>
<url>http://maven.aliyun.com/nexus/content/groups/public/</url>
</repository>
<repository>
<id>cloudera</id>
<url>https://repository.cloudera.com/artifactory/cloudera-repos/</url>
</repository>
<repository>
<id>jboss</id>
<url>http://repository.jboss.com/nexus/content/groups/public</url>
</repository>
</repositories>
<!-- 版本属性 -->
<properties>
<maven.compiler.source>1.8</maven.compiler.source>
<maven.compiler.target>1.8</maven.compiler.target>
<kudu.version>1.9.0-cdh6.2.1</kudu.version>
<junit.version>4.12</junit.version>
</properties>
<dependencies>
<dependency>
<groupId>org.apache.kudu</groupId>
<artifactId>kudu-client</artifactId>
<version>${kudu.version}</version>
</dependency>
<dependency>
<groupId>org.apache.kudu</groupId>
<artifactId>kudu-client-tools</artifactId>
<version>${kudu.version}</version>
</dependency>
<dependency>
<groupId>junit</groupId>
<artifactId>junit</artifactId>
<version>4.12</version>
</dependency>
</dependencies>
<build>
<plugins>
<plugin>
<groupId>org.apache.maven.plugins</groupId>
<artifactId>maven-compiler-plugin</artifactId>
<version>3.1</version>
<configuration>
<source>1.8</source>
<target>1.8</target>
</configuration>
</plugin>
</plugins>
</build>
代码实现
// 定声明KuduClient实例对象
private KuduClient kuduClient ;
@Before
public void init() {
String masterAddresses = "node2.itcast.cn:7051" ;
// 构建KuduClient实例对象，连接Kudu集群（Kudu Master）
kuduClient = new KuduClient.KuduClientBuilder(masterAddresses)
.defaultSocketReadTimeoutMs(10000) // 设置连接Socket超时时间
.defaultOperationTimeoutMs(10000)
.build();
}
案例二：Java 操作 Kudu之创建KuduTable
/**
* 用于构建Kudu表中每列的字段信息Schema
*
* @param name 字段名称
* @param type 字段类型
* @param isKey 是否为Key
* @return ColumnSchema对象
*/
private ColumnSchema newColumnSchema(String name, Type type, boolean isKey) {
// 创建ColumnSchemaBuilder实例对象
ColumnSchema.ColumnSchemaBuilder column = new ColumnSchema.ColumnSchemaBuilder(name, type);
// 设置是否为主键
column.key(isKey) ;
// 构建 ColumnSchema
return column.build() ;
}
/**
* 创建Kudu中的表，表的结构如下所示：
create table itcast_users(
id int,
name string,
age byte,
primary key(id)
)
paritition by hash(id) partitions 3
stored as kudu ;
*/
@Test
public void createKuduTable() throws KuduException {
// a. 定义Kudu表的Schema信息
// 定义Kudu表每列Schema信息
List<ColumnSchema> columns = new ArrayList<>();
columns.add(new ColumnSchema.ColumnSchemaBuilder("id", Type.INT32).key(true).build());
columns.add(newColumnSchema("name", Type.STRING, false));
columns.add(newColumnSchema("age", Type.INT8, false));
Schema schema = new Schema(columns) ;
// b. 定义Kudu表的属性，分区策略，分区数目和副本数
CreateTableOptions options = new CreateTableOptions() ;
// 设置分区策略
options.addHashPartitions(Collections.singletonList("id"), 3);
// 设置副本数目
options.setNumReplicas(1) ;
/*
public KuduTable createTable(String name, Schema schema, CreateTableOptions builder)
*/
KuduTable kuduTable = kuduClient.createTable("itcast_users", schema, options);
System.out.println("TableId: " + kuduTable.getTableId());
}
案例三：Java 操作 Kudu之修改表中字段，增加列：address，String
/**
* 对Kudu中表进行修改，增加列：address，String
*/
@Test
public void alterKuduTableAddColumn() throws KuduException {
// 添加一列：gender
AlterTableOptions ato = new AlterTableOptions() ;
//ato.addColumn(newColumnSchema("gender", Type.STRING, false)) ;
ato.addColumn("gender", Type.STRING, "male") ;
// public AlterTableResponse alterTable(String name, AlterTableOptions ato)
AlterTableResponse response = kuduClient.alterTable("itcast_users", ato);
System.out.println(response.getTableId());
}
案例四：对Kudu表进行修改，删除列：address
@Test
public void alterKuduTableDropColumn() throws KuduException {
// 删除：gender
AlterTableOptions ato = new AlterTableOptions() ;
ato.dropColumn("gender") ;
// public AlterTableResponse alterTable(String name, AlterTableOptions ato)
AlterTableResponse response = kuduClient.alterTable("itcast_users", ato);
System.out.println(response.getTableId());
}
案例五：对Kudu表中进行插入数据
将数据插入到Kudu Table中： INSERT INTO (id, name, age) VALUES (1001, "zhangsan", 26)
@Test
public void insertKuduDataSingle() throws KuduException {
// a. 获取Kudu表的句柄，传递表的名称
KuduTable kuduTable = kuduClient.openTable("itcast_users") ;
// b. 获取KuduSession会话对象
KuduSession kuduSession = kuduClient.newSession();
// c. 构建Insert插入对象
Insert insert = kuduTable.newInsert();
// 获取Row对象，设置插入的值
PartialRow row = insert.getRow();
row.addInt("id", 1);
row.addString("name", "itcast");
row.addByte("age", (byte)15);
// d. 执行插入数据
OperationResponse response = kuduSession.apply(insert);
System.out.println(response.getElapsedMillis());
// e. 关闭
kuduSession.close();
}
案例六：批量数据插入kudu表中
@Test
public void insertKuduData() throws KuduException {
// a. 获取Kudu表的句柄，传递表的名称
KuduTable kuduTable = kuduClient.openTable("itcast_users") ;
// b. 获取KuduSession会话对象
KuduSession kuduSession = kuduClient.newSession();
// 设置批量插入数据
kuduSession.setFlushMode(SessionConfiguration.FlushMode.MANUAL_FLUSH); // 手动提交，插入数据
kuduSession.setMutationBufferSpace(1000); // 批量插入数据条目数
// FOR循环，遍历100次，插入100条数据
Random random = new Random() ;
for (int i = 1 ; i <= 100; i ++){
// c. 构建Insert插入对象
Insert insert = kuduTable.newInsert();
// 获取Row对象，设置插入的值
PartialRow row = insert.getRow();
row.addInt("id", 1000 + i);
row.addString("name", "zhangsan-" + i);
row.addByte("age", (byte)(random.nextInt(10) + 20));
// d. 加入批次中
kuduSession.apply(insert) ;
}
// 手动进行触发插入数据：刷新
kuduSession.flush();
// e. 关闭
kuduSession.close();
}
案例七：从Kudu表中全量加载数据
@Test
public void selectKuduData() throws KuduException {
// a. 获取Kudu Table的句柄，依据表的名称
KuduTable kuduTable = kuduClient.openTable("itcast_users");
// b. 构建表的扫描器对象Scanner
KuduScanner.KuduScannerBuilder builder = kuduClient.newScannerBuilder(kuduTable);
KuduScanner scanner = builder.build();
// c. 遍历数据
int counter = 1;
while (scanner.hasMoreRows()){ // 表示遍历每个Tablet数据
System.out.println("===================" + (counter ++) + "===================");
RowResultIterator rowResults = scanner.nextRows();
// 遍历Tablet中每条数据
while (rowResults.hasNext()){
RowResult rowResult = rowResults.next();
System.out.println(
"id = " + rowResult.getInt("id")
+ ", name = " + rowResult.getString("name")
+ ", age = " + rowResult.getByte("age")
);
}
}
}
案例八：从Kudu表中设置过滤查询数据
设置过滤：比如只查询id和age两个字段的值，年龄age小于25，id大于1050
/**
* 用于构建Kudu表中每列的字段信息Schema
*
* @param name 字段名称
* @param type 字段类型
* @param isKey 是否为Key
* @return ColumnSchema对象
*/
private ColumnSchema newColumnSchema(String name, Type type, boolean isKey) {
// 创建ColumnSchemaBuilder实例对象
ColumnSchema.ColumnSchemaBuilder column = new ColumnSchema.ColumnSchemaBuilder(name, type);
// 设置是否为主键
column.key(isKey) ;
// 构建 ColumnSchema
return column.build() ;
}
@Test
public void queryKuduData() throws KuduException {
// a. 获取Kudu Table的句柄，依据表的名称
KuduTable kuduTable = kuduClient.openTable("itcast_users");
// b. 构建表的扫描器对象Scanner
KuduScanner.KuduScannerBuilder builder = kuduClient.newScannerBuilder(kuduTable);
// TODO：设置选取的字段project投影
builder.setProjectedColumnNames(Arrays.asList("id", "age")) ;
// TODO: 设置过滤条件
// id大于1050
KuduPredicate idPredicate = KuduPredicate.newComparisonPredicate(
newColumnSchema("id", Type.INT32, true), //
KuduPredicate.ComparisonOp.GREATER, //
1050 //
) ;
builder.addPredicate(idPredicate) ;
// 年龄age小于25
KuduPredicate agePredicate = KuduPredicate.newComparisonPredicate(
newColumnSchema("age", Type.INT8, false), //
KuduPredicate.ComparisonOp.LESS, //
(byte)25 //
) ;
builder.addPredicate(agePredicate) ;
KuduScanner scanner = builder.build();
// c. 遍历数据
int counter = 1;
while (scanner.hasMoreRows()){ // 表示遍历每个Tablet数据
System.out.println("===================" + (counter ++) + "===================");
RowResultIterator rowResults = scanner.nextRows();
// 遍历Tablet中每条数据
while (rowResults.hasNext()){
RowResult rowResult = rowResults.next();
System.out.println(
"id = " + rowResult.getInt("id")
+ ", age = " + rowResult.getByte("age")
);
}
}
}
案例九：更新kudu表中的数据
/**
* 更新Kudu表中数据
*/
@Test
public void updateKuduData() throws KuduException {
// a. 获取Kudu表的句柄，传递表的名称
KuduTable kuduTable = kuduClient.openTable("itcast_users") ;
// b. 获取KuduSession会话对象
KuduSession kuduSession = kuduClient.newSession();
// c. 构建Update更新对象
Update update = kuduTable.newUpdate();
// 获取Row对象，设置插入的值
PartialRow row = update.getRow();
row.addInt("id", 1);
row.addString("name", "czxy");
row.addByte("age", (byte)5);
// d. 执行插入数据
OperationResponse response = kuduSession.apply(update);
System.out.println(response.getElapsedMillis());
// e. 关闭
kuduSession.close();
}
案例十：更新Kudu表中数据，当主键存在时，更新数据；不存在时，插入数据
@Test
public void upsertKuduData() throws KuduException {
// a. 获取Kudu表的句柄，传递表的名称
KuduTable kuduTable = kuduClient.openTable("itcast_users") ;
// b. 获取KuduSession会话对象
KuduSession kuduSession = kuduClient.newSession();
// c. 构建Upsert对象
Upsert upsert = kuduTable.newUpsert();
// 获取Row对象，设置插入的值
PartialRow row = upsert.getRow();
row.addInt("id", 1);
row.addString("name", "czxy");
row.addByte("age", (byte)5);
// d. 执行插入数据
OperationResponse response = kuduSession.apply(upsert);
System.out.println(response.getElapsedMillis());
// e. 关闭
kuduSession.close();
}
案例十一：删除Kudu表中数据
@Test
public void deleteKuduData() throws KuduException {
// a. 获取Kudu表的句柄，传递表的名称
KuduTable kuduTable = kuduClient.openTable("itcast_users") ;
// b. 获取KuduSession会话对象
KuduSession kuduSession = kuduClient.newSession();
// c. 构建Delete删除对象
Delete delete = kuduTable.newDelete();
// 获取Row对象，设置插入的值
PartialRow row = delete.getRow();
row.addInt("id", 1);
// d. 执行插入数据
OperationResponse response = kuduSession.apply(delete);
System.out.println(response.getElapsedMillis());
// e. 关闭
kuduSession.close();
}
