You have to build job with JobbuilderFactory:

    @Configuration
@EnableBatchProcessing
public class BatchConfiguration {

    @Autowired
    public JobBuilderFactory jobBuilderFactory;

    @Autowired
    public StepBuilderFactory stepBuilderFactory;

    @Bean
    public SomeReader<Some> reader() {

        // some reader configuration
        return reader;
    }

    @Bean
    public SomeProcessor processor() {
        return new SomeProcessor();
    }

    @Bean
    public SomeWriter<Person> writer() {
        // some config
        return writer;
    }

    @Bean
    public Job someJob() {
        return jobBuilderFactory.get("someJob")
                .flow(step1())
                .end()
                .build();
    }

    @Bean
    public Step step1() {
        return stepBuilderFactory.get("step1")
                .<Some, Some> chunk(10)
                .reader(reader())
                .processor(processor())
                .writer(writer())
                .build();
    }
    }

Start job in rest controller:

@RestController
@AllArgsConstructor
@Slf4j
public class BatchStartController {

    JobLauncher jobLauncher;

    Job job;

    @GetMapping("/job")
    public void startJob() {
    //some parameters
        Map<String, JobParameter> parameters = new HashMap<>();
        JobExecution jobExecution = jobLauncher.run(job, new JobParameters(parameters));
        }    }

And one important detail - add in application.properties:

spring.batch.job.enabled=false

to prevent job self start.

It is possible to create your own custom ItemWriter.

In your case, please add the spring-boot-starter-web dependency to either your pom.xml or build.gradle

Example:

package com.example.batch;

import lombok.extern.log4j.Log4j2;
import org.springframework.batch.item.ItemWriter;
import org.springframework.beans.factory.annotation.Autowired;
import org.springframework.http.ResponseEntity;
import org.springframework.web.client.RestTemplate;

import java.util.List;

@Log4j2
public class RestItemWriter implements ItemWriter<String> {
    @Autowired
    RestTemplate restTemplate;

    public RestItemWriter(RestTemplate restTemplate) {
        this.restTemplate = restTemplate;
    }

    @Override
    public void write(List<? extends String> items) throws Exception {
        ResponseEntity<Users> users = restTemplate.getForEntity("https://jsonplaceholder.typicode.com/users/1", Users.class);

        log.info("Status code is: " + users.getStatusCode());
    }
}


package com.example.batch;

import com.fasterxml.jackson.annotation.JsonInclude;
import lombok.Getter;
import lombok.Setter;

@Getter
@Setter
@JsonInclude(JsonInclude.Include.NON_NULL)
public class Users {

    public String id;
    public String name;
    public String username;
    public String email;
    public String phone;
}

More information about custom item writers here