Integrated tools

CREATE TABLE CAR (
     CarID INTEGER,
     CarYear INTEGER,
     CarTrade VARCHAR,
     CarNumber VARCHAR,
     PRIMARY KEY (CarID)
)

<?xml version="1.0" encoding="UTF-8"?>
<project xmlns="http://maven.apache.org/POM/4.0.0" xmlns:xsi="http://www.w3.org/2001/XMLSchema-instance" xsi:schemaLocation="http://maven.apache.org/POM/4.0.0 http://maven.apache.org/xsd/maven-4.0.0.xsd">
  <modelVersion>4.0.0</modelVersion>
  <groupId>com.leanxcale</groupId>
  <artifactId>olingo-client-example</artifactId>
  <version>0.0.1-SNAPSHOT</version>

  <packaging>jar</packaging>
  <properties>
    <project.build.sourceEncoding>UTF-8</project.build.sourceEncoding>
    <maven.compiler.source>11</maven.compiler.source>
    <maven.compiler.target>11</maven.compiler.target>
  </properties>
  <dependencies>
    <dependency>
      <groupId>org.apache.olingo</groupId>
      <artifactId>odata-client-core</artifactId>
      <version>4.5.0</version>
    </dependency>
  </dependencies>
</project>

import java.io.ByteArrayInputStream;
import java.io.InputStream;
import java.net.URI;
import org.apache.olingo.client.api.ODataClient;
import org.apache.olingo.client.api.communication.request.cud.ODataDeleteRequest;
import org.apache.olingo.client.api.communication.request.cud.ODataEntityCreateRequest;
import org.apache.olingo.client.api.communication.request.cud.ODataEntityUpdateRequest;
import org.apache.olingo.client.api.communication.request.cud.UpdateType;
import org.apache.olingo.client.api.communication.request.retrieve.ODataEntityRequest;
import org.apache.olingo.client.api.communication.request.retrieve.ODataEntitySetIteratorRequest;
import org.apache.olingo.client.api.communication.response.ODataDeleteResponse;
import org.apache.olingo.client.api.communication.response.ODataEntityCreateResponse;
import org.apache.olingo.client.api.communication.response.ODataEntityUpdateResponse;
import org.apache.olingo.client.api.communication.response.ODataRetrieveResponse;
import org.apache.olingo.client.api.domain.ClientEntity;
import org.apache.olingo.client.api.domain.ClientEntitySet;
import org.apache.olingo.client.api.domain.ClientEntitySetIterator;
import org.apache.olingo.client.api.serialization.ODataDeserializerException;
import org.apache.olingo.client.core.ODataClientFactory;
import org.apache.olingo.commons.api.format.ContentType;

public class Main {

  private static final String SERVICE_URL = "http://localhost:8900/kivi";

  private static final String[] carsToInsert = new String[]{
      "{\"CARID\":1,\"CARYEAR\":1984,\"CARTRADE\":\"Mazda\",\"CARNUMBER\":\"IX3443\"}",
      "{\"CARID\":2,\"CARYEAR\":2002,\"CARTRADE\":\"Mazda\",\"CARNUMBER\":\"IX3443\"}",
      "{\"CARID\":3,\"CARYEAR\":2022,\"CARTRADE\":\"Mazda\",\"CARNUMBER\":\"IX3443\"}",
      "{\"CARID\":4,\"CARYEAR\":1983,\"CARTRADE\":\"Mazda\",\"CARNUMBER\":\"IX3443\"}",
      "{\"CARID\":5,\"CARYEAR\":1999,\"CARTRADE\":\"Toyota\",\"CARNUMBER\":\"IX3443\"}",
      "{\"CARID\":6,\"CARYEAR\":2008,\"CARTRADE\":\"Toyota\",\"CARNUMBER\":\"IX3443\"}",
      "{\"CARID\":7,\"CARYEAR\":2018,\"CARTRADE\":\"Toyota\",\"CARNUMBER\":\"IX3443\"}",
      "{\"CARID\":8,\"CARYEAR\":2016,\"CARTRADE\":\"Ferrari\",\"CARNUMBER\":\"IX3443\"}",
      "{\"CARID\":9,\"CARYEAR\":2021,\"CARTRADE\":\"Ferrari\",\"CARNUMBER\":\"IX3443\"}",
      "{\"CARID\":10,\"CARYEAR\":2022,\"CARTRADE\":\"Datsun\",\"CARNUMBER\":\"IX3443\"}"};

  private static final String carToUpdate = "{\"CARID\":10,\"CARTRADE\":\"Ferrari\"}";

  /**
     there is a table defined as
     CREATE TABLE CAR (
        CarID INTEGER,
        CarYear INTEGER,
        CarTrade VARCHAR,
        CarNumber VARCHAR,
        PRIMARY KEY (CarID))
   */

  public static void main(String[] args) {

    try {
      ODataClient odataClient = ODataClientFactory.getClient();
      odataClient.getConfiguration().setDefaultPubFormat(ContentType.APPLICATION_JSON);
      final String entitySetName = "Cars";

      //insert some cars
      for (int i = 0; i < 10; i++) {
        ClientEntity loadEntity = loadEntity(odataClient, carsToInsert[i]);
        URI absoluteUriImport = odataClient.newURIBuilder(SERVICE_URL).appendEntitySetSegment(entitySetName).build();
        ODataEntityCreateRequest<ClientEntity> requestCreate = odataClient.getCUDRequestFactory().getEntityCreateRequest(absoluteUriImport,
            loadEntity);
        requestCreate.setAccept("application/json");
        ODataEntityCreateResponse<ClientEntity> responseCreate = requestCreate.execute();
        responseCreate.getBody();
        System.out.println("entry loaded " + carsToInsert[i]);
      }

      //read everything from a table
      URI absoluteUri = odataClient.newURIBuilder(SERVICE_URL).appendEntitySetSegment(entitySetName).build();
      System.out.println("URI = " + absoluteUri);
      ODataEntitySetIteratorRequest<ClientEntitySet, ClientEntity> request =
          odataClient.getRetrieveRequestFactory().getEntitySetIteratorRequest(absoluteUri);
      request.setAccept("application/json");
      ODataRetrieveResponse<ClientEntitySetIterator<ClientEntitySet, ClientEntity>> response = request.execute();
      ClientEntitySetIterator<ClientEntitySet, ClientEntity> responseIterator = response.getBody();
      while (responseIterator.hasNext()) {
        printResult(responseIterator.next());
      }

      //read entity by key
      Integer keyValue = 1;
      absoluteUri = odataClient.newURIBuilder(SERVICE_URL).appendEntitySetSegment(entitySetName).appendKeySegment(keyValue).build();
      System.out.println("URI = " + absoluteUri);
      ODataEntityRequest<ClientEntity> entityRequest = odataClient.getRetrieveRequestFactory().getEntityRequest(absoluteUri);
      request.setAccept("application/json");
      ODataRetrieveResponse<ClientEntity> entityResponse = entityRequest.execute();
      ClientEntity clientEntity = entityResponse.getBody();

      printResult(clientEntity);

      //read entities by filter
      absoluteUri = odataClient.newURIBuilder(SERVICE_URL).appendEntitySetSegment(entitySetName).filter("CARTRADE eq 'Ferrari'").build();
      System.out.println("URI = " + absoluteUri);
      request = odataClient.getRetrieveRequestFactory().getEntitySetIteratorRequest(absoluteUri);
      request.setAccept("application/json");
      response = request.execute();
      responseIterator = response.getBody();
      while (responseIterator.hasNext()) {
        printResult(responseIterator.next());
      }

      //read again car10
      keyValue = 10;
      absoluteUri = odataClient.newURIBuilder(SERVICE_URL).appendEntitySetSegment(entitySetName).appendKeySegment(keyValue).build();
      System.out.println("URI = " + absoluteUri);
      entityRequest = odataClient.getRetrieveRequestFactory().getEntityRequest(absoluteUri);
      request.setAccept("application/json");
      entityResponse = entityRequest.execute();
      clientEntity = entityResponse.getBody();
      printResult(clientEntity);

      //update car10 with patch (it will only update the values in the input clientEntity
      ClientEntity updateEntity = loadEntity(odataClient, carToUpdate);
      absoluteUri = odataClient.newURIBuilder(SERVICE_URL).appendEntitySetSegment(entitySetName).appendKeySegment(keyValue).build();
      ODataEntityUpdateRequest<ClientEntity> requestUpdate = odataClient.getCUDRequestFactory().getEntityUpdateRequest(absoluteUri,
          UpdateType.PATCH, updateEntity);
      requestUpdate.setAccept("application/json;odata.metadata=minimal");
      ODataEntityUpdateResponse<ClientEntity> responseUpdate = requestUpdate.execute();
      System.out.println("Response code: " + responseUpdate.getStatusCode());

      //read now again car10
      absoluteUri = odataClient.newURIBuilder(SERVICE_URL).appendEntitySetSegment(entitySetName).appendKeySegment(keyValue).build();
      System.out.println("URI = " + absoluteUri);
      entityRequest = odataClient.getRetrieveRequestFactory().getEntityRequest(absoluteUri);
      request.setAccept("application/json");
      entityResponse = entityRequest.execute();
      clientEntity = entityResponse.getBody();
      printResult(clientEntity);

      //update car10 with PUT (it will upsert the values in the input clientEntity. missing values in the clientEntity will be 'null'
      updateEntity = loadEntity(odataClient, carToUpdate);
      absoluteUri = odataClient.newURIBuilder(SERVICE_URL).appendEntitySetSegment(entitySetName).appendKeySegment(keyValue).build();
      requestUpdate = odataClient.getCUDRequestFactory().getEntityUpdateRequest(absoluteUri, UpdateType.REPLACE, updateEntity);
      requestUpdate.setAccept("application/json;odata.metadata=minimal");
      responseUpdate = requestUpdate.execute();
      System.out.println("Response code: " + responseUpdate.getStatusCode());

      //read now again car10
      absoluteUri = odataClient.newURIBuilder(SERVICE_URL).appendEntitySetSegment(entitySetName).appendKeySegment(keyValue).build();
      System.out.println("URI = " + absoluteUri);
      entityRequest = odataClient.getRetrieveRequestFactory().getEntityRequest(absoluteUri);
      request.setAccept("application/json");
      entityResponse = entityRequest.execute();
      clientEntity = entityResponse.getBody();
      printResult(clientEntity);

      //delete now car10
      absoluteUri = odataClient.newURIBuilder(SERVICE_URL).appendEntitySetSegment(entitySetName).appendKeySegment(keyValue).build();
      ODataDeleteRequest requestDelete = odataClient.getCUDRequestFactory().getDeleteRequest(absoluteUri);
      requestDelete.setAccept("application/json;odata.metadata=minimal");
      ODataDeleteResponse responseDelete = requestDelete.execute();
      System.out.println("Response code: " + responseDelete.getStatusCode());

      //try to read again car10
      try {
        absoluteUri = odataClient.newURIBuilder(SERVICE_URL).appendEntitySetSegment(entitySetName).appendKeySegment(keyValue).build();
        System.out.println("URI = " + absoluteUri);
        entityRequest = odataClient.getRetrieveRequestFactory().getEntityRequest(absoluteUri);
        request.setAccept("application/json");
        entityRequest.execute();
      } catch (Exception ex) {
        System.out.println("car 10 does not exist");
      }
    } catch (Exception ex) {
      ex.printStackTrace();
    }
  }

  private static ClientEntity loadEntity(ODataClient odataClient, String json) throws ODataDeserializerException {
    InputStream input = new ByteArrayInputStream(json.getBytes());
    return odataClient.getBinder().getODataEntity(odataClient.getDeserializer(ContentType.APPLICATION_JSON).toEntity(input));
  }

  private static void printResult(ClientEntity clientEntity) {
    clientEntity.getProperties().forEach((t) -> {
      System.out.print(t.getName() + ":");
      System.out.print(t.getValue() + " - ");
    });
    System.out.println();
  }
}