HBase of java operation, the latest API. (Query specified row, column, insert data, etc.)

HBase HBase environment and to build on the principles of architecture, see the related blog author.

1.HBase has a more excellent support for java, this article describes how to use java operations Hbase.

First pom-dependent:

<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>
<the artifactId> log4j </ the artifactId>
<Version> 1.2.17 </ Version>
</ dependency>
HBase 2. operation key classes:

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", "[email protected]");
insertData("user_table", user);
User user2 = new User("002", "xiaohong", "654321", "female", "18", "18757912212", "[email protected]");
insertData("user_table", user2);
List<User> list = getAllData("user_table");
System.out.println("After inserting the two data -------------------- -------------------- "); }System.out.println (user3.toString ());
for ( USER3 the User: List) {


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", "[email protected]");
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. Test results as shown below:}
}

 

java operating HBase success
---------------------
Author: also heart _yan
Original: https: //blog.csdn.net/m0_38075425/article/details/81287836

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Origin www.cnblogs.com/leon0/p/11130499.html