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Thread: Using JpaRepository in a class implementing Runnable

  1. #1
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    Question Using JpaRepository in a class implementing Runnable

    I'm creating a socket server using Spring Boot and I'm having trouble initializing my JpaRepositories in a class that implements Runnable. For testing the server I use Netcat and the server successfully receives the data and creates a new thread to handle/parse the data. But when the time comes to save the data in the database via JpaRepositories I get NullPointerException since repositories have not been successfully initialized. What I'm am I missing in my configuration for this to work?

    My SpringBootApplication

    package is.siminn.aos;
     
    import java.net.ServerSocket;
     
    import org.apache.logging.log4j.Level;
    import org.apache.logging.log4j.LogManager;
    import org.apache.logging.log4j.Logger;
    import org.springframework.boot.SpringApplication;
    import org.springframework.boot.autoconfigure.SpringBootApplication;
     
    @SpringBootApplication
    public class AosApplication {
        public static final Logger log = LogManager.getLogger(AosApplication.class);
     
        public static void main(String[] args) {
            SpringApplication.run(AosApplication.class, args);
            openSocket();
        }
     
        private static void openSocket() {
            try (ServerSocket server = new ServerSocket(1234)) {
                log.log(Level.INFO, "Server listening on port " + 1234);
                while (true) {
                    Thread obj = new Thread(new AosTask(server.accept()));
                    obj.start();
                }
            } catch (Exception e) {
                log.log(Level.ERROR, e.getMessage(), e);
            }
        }
    }

    Class implementing Runnable

    package is.siminn.aos;
     
    import java.io.InputStreamReader;
    import java.io.OutputStreamWriter;
    import java.net.Socket;
    import java.util.Date;
     
    import javax.transaction.Transactional;
     
    import org.apache.logging.log4j.Level;
    import org.apache.logging.log4j.LogManager;
    import org.apache.logging.log4j.Logger;
     
    import is.siminn.aos.domain.Alarm;
    import is.siminn.aos.domain.AlarmCategory;
    import is.siminn.aos.domain.AlarmClass;
    import is.siminn.aos.domain.Exchange;
    import is.siminn.aos.domain.Spr;
    import is.siminn.aos.repositories.AlarmCategoryRepository;
    import is.siminn.aos.repositories.AlarmClassRepository;
    import is.siminn.aos.repositories.AlarmRepository;
    import is.siminn.aos.repositories.ExchangeRepository;
    import is.siminn.aos.repositories.SprRepository;
    import is.siminn.aos.repositories.SubExchangeRepository;
     
    public class AosTask implements Runnable {
     
        public static final Logger log = LogManager.getLogger(AosTask.class);
     
        Socket socket;
     
        AlarmClassRepository alarmClassRepository;
     
        AlarmCategoryRepository alarmCategoryRepository;
     
        ExchangeRepository exchangeRepository;
     
        SubExchangeRepository subExchangeRepository;
     
        SprRepository sprRepository;
     
        AlarmRepository alarmRepository;
     
        protected AosTask(Socket socket) {
            this.socket = socket;
        }
     
        @Override
        public void run() {
            System.out.println("Thread " + Thread.currentThread().getId() + " is running");
            int ascii = -1;
     
            try (InputStreamReader in = new InputStreamReader(socket.getInputStream())) {
                OutputStreamWriter out = new OutputStreamWriter(socket.getOutputStream());
                StringBuffer axeBlock = new StringBuffer();
     
                do {
                    ascii = in.read();
                    axeBlock.append((char) ascii);
                } while (ascii != 4);
                out.append(process(axeBlock));
                out.flush();
     
            } catch (Exception e) {
                log.log(Level.ERROR, e.getMessage(), e);
            } finally {
                try {
                    socket.close();
                } catch (Exception e) {
                    log.log(Level.ERROR, e.getMessage(), e);
                }
            }
        }
     
        @Transactional
        private String process(StringBuffer axeBlock) {
            String header1 = "";
            String header2 = "";
            Alarm alarm = null;
            boolean isAlarm = true;
     
            String[] axeBlockArray = axeBlock.toString().split("\\n|\\r|\\f");
            for (int i = 0; i < axeBlockArray.length; i++) {
                String line = axeBlockArray[i];
     
     
                if (line.startsWith(":type=alarm") || line.startsWith(":type=spontan")) { /* APG type */
                    log.log(Level.DEBUG, "APG...");
     
                    if (line.startsWith(":type=alarm")) {
                        String nextLine = axeBlockArray[i + 2];
     
                        if (nextLine.startsWith("*** ALARM CEASING")) {
                            log.log(Level.DEBUG, "APG alarm ceasing");
                            isAlarm = false;
                            ceasing(nextLine);
                            break;
                        } else {
                            log.log(Level.DEBUG, "APG alarm");
                            header1 = nextLine;
                            alarm = alarm(header1);
                            header2 = axeBlockArray[i + 3];
                            break;
                        }
     
                    } else if (line.startsWith("type=spontan")) {
                        log.log(Level.DEBUG, "APG heartbeat");
                        System.out.println("heartbeat");
                        isAlarm = false;
                        heartbeat(line);
                        break;
                    } else {
                        /* wtf */
                    }
                    break;
                } else if (line.startsWith("WO      ")) { /* IOG type */
                    log.log(Level.DEBUG, "IOG...");
                    // TODO: implement
                } else {
                    /* nothing to see here */
                }
            }
     
            if (isAlarm) {
                alarm.setSpr(new Spr(header1, header2, new String[] {axeBlock.toString()}));
            }
            return axeBlock.toString();
        }
     
        private Alarm alarm(String header1) {
            Alarm alarm = new Alarm();
     
            /**
             * Header example
             * header1: *** ALARM 406 A2/APT "TBREI/IS76/MPS1"A 220104 1404
             */
            String[] fields = header1.split(" ");
     
            Integer alarmId = Integer.valueOf(fields[2]);
            String[] alarmClassAndCategory = fields[3].split("/");
            String cls = alarmClassAndCategory[0];
            String cat = alarmClassAndCategory[1];
            String exch = fields[4].substring(1, fields[4].indexOf("/"));
            String date = fields[5];
            String time = fields[6];
            Date created = null;
            try {
                created = Utils.createTimestamp(date, time);
            } catch (Exception e) {
                // TODO: handle exception
            }
     
            AlarmClass alarmClass = alarmClassRepository.findByCode(cls);
            AlarmCategory alarmCategory = alarmCategoryRepository.findByCode(cat);
            Exchange exchange = exchangeRepository.findByCode(exch);
     
            alarm.setAlarmId(alarmId);
            alarm.setAlarmCategory(alarmCategory);
            alarm.setAlarmClass(alarmClass);
            alarm.setExchange(exchange);
            alarm.setDateCreated(created);
     
            return alarm;
        }
     
        private void ceasing(String line) {
            log.log(Level.DEBUG, "CEASING [" + line + "]");
            // TODO: implement
        }
     
        private void heartbeat(String line) {
            log.log(Level.DEBUG, "HEARTBEAT [" + line + "]");
            // TODO: implement
        }
    }

    application.properties

    # ===============================
    # = DATA SOURCE
    # ===============================
    # Set here configurations for the database connection
    spring.datasource.url=jdbc:postgresql://localhost:5432/aos
    spring.datasource.username=foo
    spring.datasource.password=bar
    spring.datasource.driver-class-name=org.postgresql.Driver
    # Keep the connection alive if idle for a long time (needed in production)
    spring.datasource.tomcat.test-while-idle=true
    spring.datasource.tomcat.validation-query=SELECT 1
     
     
    # ===============================
    # = JPA / HIBERNATE
    # ===============================
    # Show or not log for each sql query
    spring.jpa.show-sql=true
    # Hibernate ddl auto (create, create-drop, update): with "create" the database
    spring.jpa.hibernate.ddl-auto=create
    #spring.jpa.hibernate.ddl-auto=update
     
    # Naming strategy
    spring.jpa.hibernate.naming.implicit-strategy=org.hibernate.boot.model.naming.ImplicitNamingStrategyLegacyHbmImpl
    spring.jpa.hibernate.naming.physical-strategy=org.springframework.boot.orm.jpa.hibernate.SpringPhysicalNamingStrategy
     
    # Allows Hibernate to generate SQL optimized for a particular DBMS
    spring.jpa.properties.hibernate.dialect=org.hibernate.dialect.PostgreSQLDialect
    spring.main.allow-bean-definition-overriding=true

    I have a few repositories and they are implemented in the same way so I'll only post one example.

    package is.siminn.aos.repositories;
     
    import org.springframework.data.jpa.repository.JpaRepository;
    import org.springframework.stereotype.Repository;
     
    import is.siminn.aos.domain.AlarmCategory;
     
    @Repository
    public interface AlarmCategoryRepository extends JpaRepository<AlarmCategory, Long> {
        AlarmCategory findByCode(String code);
    }

    Entities are also all similar so I think one example is enough.

    package is.siminn.aos.domain;
     
    import java.io.Serializable;
    import java.util.Objects;
     
    import javax.persistence.Column;
    import javax.persistence.Entity;
    import javax.persistence.GeneratedValue;
    import javax.persistence.GenerationType;
    import javax.persistence.Id;
    import javax.persistence.Table;
     
    import lombok.Data;
     
    @Data
    @Entity
    @Table(name = "ALARM_CLASS")
    public class AlarmClass implements Serializable {
     
        private static final long serialVersionUID = 1L;
     
        @Id
        @Column(name = "ID", nullable = false)
        @GeneratedValue(strategy = GenerationType.IDENTITY)
        private Long id;
     
        @Column(name = "CODE", nullable = false, unique = true)
        private String code;
     
        public AlarmClass() {
            super();
            // TODO Auto-generated constructor stub
        }
     
        public AlarmClass(String code) {
            super();
            this.code = code;
        }
     
        public Long getId() {
            return id;
        }
     
        public void setId(Long id) {
            this.id = id;
        }
     
        public String getCode() {
            return code;
        }
     
        public void setCode(String code) {
            this.code = code;
        }
     
        @Override
        public int hashCode() {
            return Objects.hash(code, id);
        }
     
        @Override
        public boolean equals(Object obj) {
            if (this == obj)
                return true;
            if (obj == null)
                return false;
            if (getClass() != obj.getClass())
                return false;
            AlarmClass other = (AlarmClass) obj;
            return Objects.equals(code, other.code) && id == other.id;
        }
     
        @Override
        public String toString() {
            return "AlarmClass [id=" + id + ", code=" + code + "]";
        }
     
    }

    SpringApplication log

    12:36:16.752 [Thread-0] DEBUG org.springframework.boot.devtools.restart.classloader.RestartClassLoader - Created RestartClassLoader org.springframework.boot.devtools.restart.classloader.RestartClassLoader@79f54323
     
      .   ____          _            __ _ _
     /\\ / ___'_ __ _ _(_)_ __  __ _ \ \ \ \
    ( ( )\___ | '_ | '_| | '_ \/ _` | \ \ \ \
     \\/  ___)| |_)| | | | | || (_| |  ) ) ) )
      '  |____| .__|_| |_|_| |_\__, | / / / /
     =========|_|==============|___/=/_/_/_/
     :: Spring Boot ::                (v2.6.2)
     
    2022-01-14 12:36:16.997  INFO 65870 --- [  restartedMain] is.siminn.aos.AosApplication             : Starting AosApplication using Java 15.0.1 on IS-C02F62LZMD6R with PID 65870 (/Users/gsigurdsson/Documents/workspace-spring-tool-suite-4-4.8.0.RELEASE/aos/target/classes started by gsigurdsson in /Users/gsigurdsson/Documents/workspace-spring-tool-suite-4-4.8.0.RELEASE/aos)
    2022-01-14 12:36:16.998  INFO 65870 --- [  restartedMain] is.siminn.aos.AosApplication             : No active profile set, falling back to default profiles: default
    2022-01-14 12:36:17.027  INFO 65870 --- [  restartedMain] .e.DevToolsPropertyDefaultsPostProcessor : Devtools property defaults active! Set 'spring.devtools.add-properties' to 'false' to disable
    2022-01-14 12:36:17.337  INFO 65870 --- [  restartedMain] .s.d.r.c.RepositoryConfigurationDelegate : Multiple Spring Data modules found, entering strict repository configuration mode!
    2022-01-14 12:36:17.338  INFO 65870 --- [  restartedMain] .s.d.r.c.RepositoryConfigurationDelegate : Bootstrapping Spring Data JDBC repositories in DEFAULT mode.
    2022-01-14 12:36:17.357  INFO 65870 --- [  restartedMain] .RepositoryConfigurationExtensionSupport : Spring Data JDBC - Could not safely identify store assignment for repository candidate interface is.siminn.aos.repositories.AlarmCategoryRepository. If you want this repository to be a JDBC repository, consider annotating your entities with one of these annotations: org.springframework.data.relational.core.mapping.Table.
    2022-01-14 12:36:17.359  INFO 65870 --- [  restartedMain] .RepositoryConfigurationExtensionSupport : Spring Data JDBC - Could not safely identify store assignment for repository candidate interface is.siminn.aos.repositories.AlarmClassRepository. If you want this repository to be a JDBC repository, consider annotating your entities with one of these annotations: org.springframework.data.relational.core.mapping.Table.
    2022-01-14 12:36:17.360  INFO 65870 --- [  restartedMain] .RepositoryConfigurationExtensionSupport : Spring Data JDBC - Could not safely identify store assignment for repository candidate interface is.siminn.aos.repositories.AlarmRepository. If you want this repository to be a JDBC repository, consider annotating your entities with one of these annotations: org.springframework.data.relational.core.mapping.Table.
    2022-01-14 12:36:17.362  INFO 65870 --- [  restartedMain] .RepositoryConfigurationExtensionSupport : Spring Data JDBC - Could not safely identify store assignment for repository candidate interface is.siminn.aos.repositories.AosUserRepository. If you want this repository to be a JDBC repository, consider annotating your entities with one of these annotations: org.springframework.data.relational.core.mapping.Table.
    2022-01-14 12:36:17.363  INFO 65870 --- [  restartedMain] .RepositoryConfigurationExtensionSupport : Spring Data JDBC - Could not safely identify store assignment for repository candidate interface is.siminn.aos.repositories.ExchangeRepository. If you want this repository to be a JDBC repository, consider annotating your entities with one of these annotations: org.springframework.data.relational.core.mapping.Table.
    2022-01-14 12:36:17.365  INFO 65870 --- [  restartedMain] .RepositoryConfigurationExtensionSupport : Spring Data JDBC - Could not safely identify store assignment for repository candidate interface is.siminn.aos.repositories.HeartbeatRepository. If you want this repository to be a JDBC repository, consider annotating your entities with one of these annotations: org.springframework.data.relational.core.mapping.Table.
    2022-01-14 12:36:17.366  INFO 65870 --- [  restartedMain] .RepositoryConfigurationExtensionSupport : Spring Data JDBC - Could not safely identify store assignment for repository candidate interface is.siminn.aos.repositories.SprRepository. If you want this repository to be a JDBC repository, consider annotating your entities with one of these annotations: org.springframework.data.relational.core.mapping.Table.
    2022-01-14 12:36:17.367  INFO 65870 --- [  restartedMain] .RepositoryConfigurationExtensionSupport : Spring Data JDBC - Could not safely identify store assignment for repository candidate interface is.siminn.aos.repositories.SubExchangeRepository. If you want this repository to be a JDBC repository, consider annotating your entities with one of these annotations: org.springframework.data.relational.core.mapping.Table.
    2022-01-14 12:36:17.368  INFO 65870 --- [  restartedMain] .s.d.r.c.RepositoryConfigurationDelegate : Finished Spring Data repository scanning in 26 ms. Found 0 JDBC repository interfaces.
    2022-01-14 12:36:17.376  INFO 65870 --- [  restartedMain] .s.d.r.c.RepositoryConfigurationDelegate : Multiple Spring Data modules found, entering strict repository configuration mode!
    2022-01-14 12:36:17.377  INFO 65870 --- [  restartedMain] .s.d.r.c.RepositoryConfigurationDelegate : Bootstrapping Spring Data JPA repositories in DEFAULT mode.
    2022-01-14 12:36:17.409  INFO 65870 --- [  restartedMain] .s.d.r.c.RepositoryConfigurationDelegate : Finished Spring Data repository scanning in 29 ms. Found 8 JPA repository interfaces.
    2022-01-14 12:36:17.667  INFO 65870 --- [  restartedMain] o.hibernate.jpa.internal.util.LogHelper  : HHH000204: Processing PersistenceUnitInfo [name: default]
    2022-01-14 12:36:17.698  INFO 65870 --- [  restartedMain] org.hibernate.Version                    : HHH000412: Hibernate ORM core version 5.6.3.Final
    2022-01-14 12:36:17.798  INFO 65870 --- [  restartedMain] o.hibernate.annotations.common.Version   : HCANN000001: Hibernate Commons Annotations {5.1.2.Final}
    2022-01-14 12:36:17.876  INFO 65870 --- [  restartedMain] com.zaxxer.hikari.HikariDataSource       : HikariPool-1 - Starting...
    2022-01-14 12:36:18.014  INFO 65870 --- [  restartedMain] com.zaxxer.hikari.HikariDataSource       : HikariPool-1 - Start completed.
    2022-01-14 12:36:18.027  INFO 65870 --- [  restartedMain] org.hibernate.dialect.Dialect            : HHH000400: Using dialect: org.hibernate.dialect.PostgreSQLDialect
    Hibernate: drop table if exists activity cascade
    Hibernate: drop table if exists alarm cascade
    Hibernate: drop table if exists alarm_category cascade
    Hibernate: drop table if exists alarm_class cascade
    Hibernate: drop table if exists aos_user cascade
    Hibernate: drop table if exists exchange cascade
    Hibernate: drop table if exists heartbeat cascade
    Hibernate: drop table if exists preferences cascade
    Hibernate: drop table if exists spr cascade
    Hibernate: drop table if exists sub_exchange cascade
    Hibernate: create table activity (id  bigserial not null, alarm_id bytea not null, aosuser_id bytea not null, created timestamp not null, message varchar(2048), updated timestamp not null, primary key (id))
    Hibernate: create table alarm (id  bigserial not null, alarm_category bytea not null, alarm_class bytea not null, alarm_id int4 not null, ceasing_time timestamp, date_created timestamp not null, exchange_id bytea not null, spr_id bytea not null, primary key (id))
    Hibernate: create table alarm_category (id  bigserial not null, code varchar(255) not null, primary key (id))
    Hibernate: create table alarm_class (id  bigserial not null, code varchar(255) not null, primary key (id))
    Hibernate: create table aos_user (id  bigserial not null, user_name varchar(255) not null, primary key (id))
    Hibernate: create table exchange (id  bigserial not null, code varchar(255) not null, primary key (id))
    Hibernate: create table heartbeat (id  bigserial not null, exchange_id bytea, lastcall timestamp not null, primary key (id))
    Hibernate: create table preferences (id  bigserial not null, aosuser_id bytea not null, paging_counter int4 not null, refresh_interval int4 not null, primary key (id))
    Hibernate: create table spr (id  bigserial not null, header1 varchar(255) not null, header2 varchar(255) not null, message bytea not null, primary key (id))
    Hibernate: create table sub_exchange (id  bigserial not null, code varchar(255) not null, exchange_id bytea not null, primary key (id))
    Hibernate: alter table alarm_category add constraint UK_k23l5xnesa680kk6b7sfeo2tt unique (code)
    Hibernate: alter table alarm_class add constraint UK_he7nncsa3mlq6baqdjyg8hycy unique (code)
    Hibernate: alter table aos_user add constraint UK_kbd1svuqgedu877c6x9n0hspd unique (user_name)
    Hibernate: alter table exchange add constraint UK_84nwdtjn33htwaelm1fun3s7r unique (code)
    Hibernate: alter table sub_exchange add constraint UK_s46mwccobp5ktr1yh2o491uoo unique (code)
    2022-01-14 12:36:18.732  INFO 65870 --- [  restartedMain] o.h.t.schema.internal.SchemaCreatorImpl  : HHH000476: Executing import script 'file:/Users/gsigurdsson/Documents/workspace-spring-tool-suite-4-4.8.0.RELEASE/aos/target/classes/import.sql'
    Hibernate: INSERT INTO alarm_category (code) VALUES('APZ')
    Hibernate: INSERT INTO alarm_category (code) VALUES('APT')
    Hibernate: INSERT INTO alarm_category (code) VALUES('POWER')
    Hibernate: INSERT INTO alarm_category (code) VALUES('EXT')
    Hibernate: INSERT INTO alarm_class (code) VALUES('A1')
    Hibernate: INSERT INTO alarm_class (code) VALUES('A2')
    Hibernate: INSERT INTO alarm_class (code) VALUES('A3')
    Hibernate: INSERT INTO alarm_class (code) VALUES('O1')
    Hibernate: INSERT INTO alarm_class (code) VALUES('O2')
    Hibernate: INSERT INTO alarm_class (code) VALUES('O3')
    Hibernate: INSERT INTO exchange (code) VALUES('SMUT')
    Hibernate: INSERT INTO exchange (code) VALUES('SBRE')
    Hibernate: INSERT INTO exchange (code) VALUES('TBREI')
    Hibernate: INSERT INTO exchange (code) VALUES('AKUR')
    Hibernate: INSERT INTO exchange (code) VALUES('BREI')
    Hibernate: INSERT INTO exchange (code) VALUES('EGIL')
    Hibernate: INSERT INTO exchange (code) VALUES('ISAF')
    Hibernate: INSERT INTO exchange (code) VALUES('KOPA')
    Hibernate: INSERT INTO exchange (code) VALUES('MIDB')
    Hibernate: INSERT INTO exchange (code) VALUES('MULI')
    Hibernate: INSERT INTO exchange (code) VALUES('SELF')
    Hibernate: INSERT INTO exchange (code) VALUES('VARM')
    Hibernate: INSERT INTO exchange (code) VALUES('TMULI')
    Hibernate: INSERT INTO exchange (code) VALUES('PRUF')
    2022-01-14 12:36:18.922  INFO 65870 --- [  restartedMain] o.h.e.t.j.p.i.JtaPlatformInitiator       : HHH000490: Using JtaPlatform implementation: [org.hibernate.engine.transaction.jta.platform.internal.NoJtaPlatform]
    2022-01-14 12:36:18.928  INFO 65870 --- [  restartedMain] j.LocalContainerEntityManagerFactoryBean : Initialized JPA EntityManagerFactory for persistence unit 'default'
    2022-01-14 12:36:19.368  INFO 65870 --- [  restartedMain] o.s.b.d.a.OptionalLiveReloadServer       : LiveReload server is running on port 35729
    2022-01-14 12:36:19.385  INFO 65870 --- [  restartedMain] is.siminn.aos.AosApplication             : Started AosApplication in 2.625 seconds (JVM running for 3.313)
    2022-01-14 12:36:19.388  INFO 65870 --- [  restartedMain] is.siminn.aos.AosApplication             : Server listening on port 1234
    Thread 43 is running
    2022-01-14 12:39:02.194 ERROR 65870 --- [       Thread-7] is.siminn.aos.AosTask                    : Cannot invoke "is.siminn.aos.repositories.AlarmClassRepository.findByCode(String)" because "this.alarmClassRepository" is null
     
    java.lang.NullPointerException: Cannot invoke "is.siminn.aos.repositories.AlarmClassRepository.findByCode(String)" because "this.alarmClassRepository" is null
        at is.siminn.aos.AosTask.alarm(AosTask.java:157) ~[classes/:na]
        at is.siminn.aos.AosTask.process(AosTask.java:105) ~[classes/:na]
        at is.siminn.aos.AosTask.run(AosTask.java:65) ~[classes/:na]
        at java.base/java.lang.Thread.run(Thread.java:832) ~[na:an]


    ----------------------
    code from Java Testing Tools.

  2. #2
    Super Moderator Norm's Avatar
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    Default Re: Using JpaRepository in a class implementing Runnable

    Sorry, I do not know anything about any of those frameworks or systems.
    Try asking on another forum like this one: http://www.coderanch.com/forums
    If you don't understand my answer, don't ignore it, ask a question.

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