How to pass Uploaded Multipart File as resource to Spring Batch Configuration

I want to convert csv file contains employee data to List and insert into database. I have gone through many examples from various sources, none of them provides answer for batch processing csv files uploaded from Web UI using spring batch. All examples process csv files located in resource folder (classpath). Please help me to process csv files uploaded using Post Method as below.

package com.techprimers.springbatchexample1.controller;

import org.springframework.batch.core.*;
import org.springframework.batch.core.launch.JobLauncher;
import org.springframework.batch.core.repository.JobExecutionAlreadyRunningException;
import org.springframework.batch.core.repository.JobInstanceAlreadyCompleteException;
import org.springframework.batch.core.repository.JobRestartException;
import org.springframework.beans.factory.annotation.Autowired;
import org.springframework.web.bind.annotation.PostMapping;
import org.springframework.web.bind.annotation.RequestMapping;
import org.springframework.web.bind.annotation.RequestParam;
import org.springframework.web.bind.annotation.RestController;
import org.springframework.web.multipart.MultipartFile;

import java.util.HashMap;
import java.util.Map;

@RestController
@RequestMapping("/load")
public class LoadController {

    @Autowired
    JobLauncher jobLauncher;

    @Autowired
    Job job;

    @PostMapping
    public BatchStatus load(@RequestParam("uploadfile") MultipartFile file) throws JobParametersInvalidException, JobExecutionAlreadyRunningException, JobRestartException, JobInstanceAlreadyCompleteException {
        **// I want file to be considered as resource to be saved to database.**
        Map<String, JobParameter> maps = new HashMap<>();
        maps.put("time", new JobParameter(System.currentTimeMillis()));
        JobParameters parameters = new JobParameters(maps);
        JobExecution jobExecution = jobLauncher.run(job, parameters);

        System.out.println("JobExecution: " + jobExecution.getStatus());

        System.out.println("Batch is Running...");
        while (jobExecution.isRunning()) {
            System.out.println("...");
        }

        return jobExecution.getStatus();
    }
}


package com.techprimers.springbatchexample1.config;

import com.techprimers.springbatchexample1.model.User;
import org.springframework.batch.core.Job;
import org.springframework.batch.core.Step;
import org.springframework.batch.core.configuration.annotation.EnableBatchProcessing;
import org.springframework.batch.core.configuration.annotation.JobBuilderFactory;
import org.springframework.batch.core.configuration.annotation.StepBuilderFactory;
import org.springframework.batch.core.launch.support.RunIdIncrementer;
import org.springframework.batch.item.ItemProcessor;
import org.springframework.batch.item.ItemReader;
import org.springframework.batch.item.ItemWriter;
import org.springframework.batch.item.file.FlatFileItemReader;
import org.springframework.batch.item.file.LineMapper;
import org.springframework.batch.item.file.mapping.BeanWrapperFieldSetMapper;
import org.springframework.batch.item.file.mapping.DefaultLineMapper;
import org.springframework.batch.item.file.transform.DelimitedLineTokenizer;
import org.springframework.context.annotation.Bean;
import org.springframework.context.annotation.Configuration;
import org.springframework.core.io.FileSystemResource;
import org.springframework.web.multipart.MultipartFile;

@Configuration
@EnableBatchProcessing
public class SpringBatchConfig {

    @Bean
    public Job job(JobBuilderFactory jobBuilderFactory,
                   StepBuilderFactory stepBuilderFactory,
                   ItemReader<User> itemReader,
                   ItemProcessor<User, User> itemProcessor,
                   ItemWriter<User> itemWriter
    ) {

        Step step = stepBuilderFactory.get("ETL-file-load")
                .<User, User>chunk(100)
                .reader(itemReader)
                .processor(itemProcessor)
                .writer(itemWriter)
                .build();


        return jobBuilderFactory.get("ETL-Load")
                .incrementer(new RunIdIncrementer())
                .start(step)
                .build();
    }

    @Bean
    public FlatFileItemReader<User> itemReader() {
        FlatFileItemReader<User> flatFileItemReader = new FlatFileItemReader<>();
        flatFileItemReader.setResource(new FileSystemResource("C:/users.csv")); **// Here, instead of reading file from disc, I want it to be passed from LoadController**
        flatFileItemReader.setName("CSV-Reader");
        flatFileItemReader.setLinesToSkip(1);
        flatFileItemReader.setLineMapper(lineMapper());
        return flatFileItemReader;
    }

    @Bean
    public LineMapper<User> lineMapper() {
        DefaultLineMapper<User> defaultLineMapper = new DefaultLineMapper<>();
        DelimitedLineTokenizer lineTokenizer = new DelimitedLineTokenizer();

        lineTokenizer.setDelimiter(",");
        lineTokenizer.setStrict(true);
        lineTokenizer.setNames(new String[]{"id", "name", "dept", "salary"});

        BeanWrapperFieldSetMapper<User> fieldSetMapper = new BeanWrapperFieldSetMapper<>();
        fieldSetMapper.setTargetType(User.class);

        defaultLineMapper.setLineTokenizer(lineTokenizer);
        defaultLineMapper.setFieldSetMapper(fieldSetMapper);

        return defaultLineMapper;
    }
}