HBase的java操作，最新API。（查询指定行、列、插入数据等）

港控/mmm° 2022-05-18 05:19 146阅读 0赞

关于HBase环境搭建和HBase的原理架构，请见笔者相关博客。

1.HBase对java有着较优秀的支持，本文将介绍如何使用java操作Hbase。

首先是pom依赖：

<dependency>
        <groupId>org.apache.hbase</groupId>
        <artifactId>hbase-client</artifactId>
        <version>1.3.1</version>
    </dependency>
    <dependency>
        <groupId>org.apache.hbase</groupId>
        <artifactId>hbase-server</artifactId>
        <version>1.3.1</version>
    </dependency>
        <dependency>
        <groupId>org.apache.hbase</groupId>
        <artifactId>hbase-common</artifactId>
        <version>1.3.1</version>
    </dependency>
    <dependency>
        <groupId>commons-logging</groupId>
        <artifactId>commons-logging</artifactId>
        <version>1.2</version>
    </dependency>
    <dependency>
        <groupId>log4j</groupId>
        <artifactId>log4j</artifactId>
        <version>1.2.17</version>
    </dependency>

2.操作HBase的关键类：

public class HbaseDemo {
    
        private static Admin admin;
    
        public static void main(String[] args){
            try {
                  createTable("user_table", new String[] { "information", "contact" });
                  User user = new User("001", "xiaoming", "123456", "man", "20", "13355550021", "1232821@csdn.com");
                  insertData("user_table", user);
                  User user2 = new User("002", "xiaohong", "654321", "female", "18", "18757912212", "214214@csdn.com");
                  insertData("user_table", user2);
                  List<User> list = getAllData("user_table");
                  System.out.println("--------------------插入两条数据后--------------------");
                  for (User user3 : list){
                     System.out.println(user3.toString());
                  }
                  System.out.println("--------------------获取原始数据-----------------------");
                  getNoDealData("user_table");
                  System.out.println("--------------------根据rowKey查询--------------------");
                  User user4 = getDataByRowKey("user_table", "user-001");
                  System.out.println(user4.toString());
                  System.out.println("--------------------获取指定单条数据-------------------");
                  String user_phone = getCellData("user_table", "user-001", "contact", "phone");
                  System.out.println(user_phone);
                  User user5 = new User("test-003", "xiaoguang", "789012", "man", "22", "12312132214", "856832@csdn.com");
                  insertData("user_table", user5);
                  List<User> list2 = getAllData("user_table");
                  System.out.println("--------------------插入测试数据后--------------------");
                  for (User user6 : list2){
                      System.out.println(user6.toString());
                  }
                  deleteByRowKey("user_table", "user-test-003");
                  List<User> list3 = getAllData("user_table");
                  System.out.println("--------------------删除测试数据后--------------------");
                  for (User user7 : list3){
                      System.out.println(user7.toString());
                  }
            } catch (Exception e) {
                e.printStackTrace();
            }
        }
    
        //连接集群
        public static Connection initHbase() throws IOException {
    
            Configuration configuration = HBaseConfiguration.create();
            configuration.set("hbase.zookeeper.property.clientPort", "2181");
            configuration.set("hbase.zookeeper.quorum", "127.0.0.1");
            //集群配置↓
            //configuration.set("hbase.zookeeper.quorum", "101.236.39.141,101.236.46.114,101.236.46.113");
            configuration.set("hbase.master", "127.0.0.1:60000");
            Connection connection = ConnectionFactory.createConnection(configuration);
            return connection;
        }
    
        //创建表
        public static void createTable(String tableNmae, String[] cols) throws IOException {
    
            TableName tableName = TableName.valueOf(tableNmae);
            admin = initHbase().getAdmin();
            if (admin.tableExists(tableName)) {
                System.out.println("表已存在！");
            } else {
                HTableDescriptor hTableDescriptor = new HTableDescriptor(tableName);
                for (String col : cols) {
                    HColumnDescriptor hColumnDescriptor = new HColumnDescriptor(col);
                    hTableDescriptor.addFamily(hColumnDescriptor);
                }
                admin.createTable(hTableDescriptor);
            }
        }
    
        //插入数据
        public static void insertData(String tableName, User user) throws IOException {
            TableName tablename = TableName.valueOf(tableName);
            Put put = new Put(("user-" + user.getId()).getBytes());
            //参数：1.列族名  2.列名  3.值
            put.addColumn("information".getBytes(), "username".getBytes(), user.getUsername().getBytes()) ;
            put.addColumn("information".getBytes(), "age".getBytes(), user.getAge().getBytes()) ;
            put.addColumn("information".getBytes(), "gender".getBytes(), user.getGender().getBytes()) ;
            put.addColumn("contact".getBytes(), "phone".getBytes(), user.getPhone().getBytes());
            put.addColumn("contact".getBytes(), "email".getBytes(), user.getEmail().getBytes());
            //HTable table = new HTable(initHbase().getConfiguration(),tablename);已弃用
            Table table = initHbase().getTable(tablename);
            table.put(put);
        }
    
        //获取原始数据
        public static void getNoDealData(String tableName){
            try {
                Table table= initHbase().getTable(TableName.valueOf(tableName));
                Scan scan = new Scan();
                ResultScanner resutScanner = table.getScanner(scan);
                for(Result result: resutScanner){
                    System.out.println("scan:  " + result);
                }
            } catch (IOException e) {
                e.printStackTrace();
            }
        }
    
        //根据rowKey进行查询
        public static User getDataByRowKey(String tableName, String rowKey) throws IOException {
    
            Table table = initHbase().getTable(TableName.valueOf(tableName));
            Get get = new Get(rowKey.getBytes());
            User user = new User();
            user.setId(rowKey);
            //先判断是否有此条数据
            if(!get.isCheckExistenceOnly()){
                Result result = table.get(get);
                for (Cell cell : result.rawCells()){
                    String colName = Bytes.toString(cell.getQualifierArray(),cell.getQualifierOffset(),cell.getQualifierLength());
                    String value = Bytes.toString(cell.getValueArray(), cell.getValueOffset(), cell.getValueLength());
                    if(colName.equals("username")){
                        user.setUsername(value);
                    }
                    if(colName.equals("age")){
                        user.setAge(value);
                    }
                    if (colName.equals("gender")){
                        user.setGender(value);
                    }
                    if (colName.equals("phone")){
                        user.setPhone(value);
                    }
                    if (colName.equals("email")){
                        user.setEmail(value);
                    }
                }
            }
            return user;
        }
    
        //查询指定单cell内容
        public static String getCellData(String tableName, String rowKey, String family, String col){
    
            try {
                Table table = initHbase().getTable(TableName.valueOf(tableName));
                String result = null;
                Get get = new Get(rowKey.getBytes());
                if(!get.isCheckExistenceOnly()){
                    get.addColumn(Bytes.toBytes(family),Bytes.toBytes(col));
                    Result res = table.get(get);
                    byte[] resByte = res.getValue(Bytes.toBytes(family), Bytes.toBytes(col));
                    return result = Bytes.toString(resByte);
                }else{
                    return result = "查询结果不存在";
                }
            } catch (IOException e) {
                e.printStackTrace();
            }
            return "出现异常";
        }
    
        //查询指定表名中所有的数据
        public static List<User> getAllData(String tableName){
    
            Table table = null;
            List<User> list = new ArrayList<User>();
            try {
                table = initHbase().getTable(TableName.valueOf(tableName));
                ResultScanner results = table.getScanner(new Scan());
                User user = null;
                for (Result result : results){
                    String id = new String(result.getRow());
                    System.out.println("用户名:" + new String(result.getRow()));
                    user = new User();
                    for(Cell cell : result.rawCells()){
                           String row = Bytes.toString(cell.getRowArray(), cell.getRowOffset(), cell.getRowLength());
                           //String family =  Bytes.toString(cell.getFamilyArray(),cell.getFamilyOffset(),cell.getFamilyLength());
                           String colName = Bytes.toString(cell.getQualifierArray(),cell.getQualifierOffset(),cell.getQualifierLength());
                           String value = Bytes.toString(cell.getValueArray(), cell.getValueOffset(), cell.getValueLength());
                           user.setId(row);
                           if(colName.equals("username")){
                                user.setUsername(value);
                           }
                           if(colName.equals("age")){
                                user.setAge(value);
                           }
                           if (colName.equals("gender")){
                               user.setGender(value);
                           }
                           if (colName.equals("phone")){
                               user.setPhone(value);
                           }
                           if (colName.equals("email")){
                               user.setEmail(value);
                           }
                    }
                    list.add(user);
                }
            } catch (IOException e) {
                e.printStackTrace();
            }
            return list;
        }
    
        //删除指定cell数据
        public static void deleteByRowKey(String tableName, String rowKey) throws IOException {
    
            Table table = initHbase().getTable(TableName.valueOf(tableName));
            Delete delete = new Delete(Bytes.toBytes(rowKey));
            //删除指定列
            //delete.addColumns(Bytes.toBytes("contact"), Bytes.toBytes("email"));
            table.delete(delete);
        }
    
        //删除表
        public static void deleteTable(String tableName){
    
            try {
                TableName tablename = TableName.valueOf(tableName);
                admin = initHbase().getAdmin();
                admin.disableTable(tablename);
                admin.deleteTable(tablename);
            } catch (IOException e) {
                e.printStackTrace();
            }
        }
    
    }

3.本文以操作User实例为例，新手看下User类：

public class User {
    
        private String id;
        private String username;
        private String password;
        private String gender;
        private String age;
        private String phone;
        private String email;
    
        public User(String id, String username, String password, String gender, String age, String phone, String email) {
            this.id = id;
            this.username = username;
            this.password = password;
            this.gender = gender;
            this.age = age;
            this.phone = phone;
            this.email = email;
        }
    
        public User(){
    
        }
    
        public String getId() {
            return id;
        }
    
        public void setId(String id) {
            this.id = id;
        }
    
        public String getUsername() {
            return username;
        }
    
        public void setUsername(String username) {
            this.username = username;
        }
    
        public String getPassword() {
            return password;
        }
    
        public void setPassword(String password) {
            this.password = password;
        }
    
        public String getGender() {
            return gender;
        }
    
        public void setGender(String gender) {
            this.gender = gender;
        }
    
        public String getAge() {
            return age;
        }
    
        public void setAge(String age) {
            this.age = age;
        }
    
        public String getPhone() {
            return phone;
        }
    
        public void setPhone(String phone) {
            this.phone = phone;
        }
    
        public String getEmail() {
            return email;
        }
    
        public void setEmail(String email) {
            this.email = email;
        }
    
        @Override
        public String toString() {
            return "User{" +
                    "id='" + id + '\'' +
                    ", username='" + username + '\'' +
                    ", password='" + password + '\'' +
                    ", gender='" + gender + '\'' +
                    ", age='" + age + '\'' +
                    ", phone='" + phone + '\'' +
                    ", email='" + email + '\'' +
                    '}';
        }
    }

4.测试结果如下图：

![70][]

java操作HBase成功

[70]: /images/20220518/25af18fc83f547689aac471797f00d78.png