CODEWITHSUNDEEP
springjava-8streamspring-data
Twistleton
Twistleton

Reputation: 2935

Java stream: Generate objects directly from an input file and save the objects with Spring Data

I'll generate for each line from an input file a Foo object and save in the next step all the objects in the database (Spring Data JPA).

    //read file into stream
    try (Stream<String> stream = Files.lines((path), Charset.forName("ISO-8859-1"))) {

        Stream<Foo> rStream = stream.map(line -> new Foo(line));           
        rStream.forEach(line -> fooRepository.save(line));

    } catch (IOException e) {
        e.printStackTrace();
    }

I received an Unhandled exception: java.lang.Exception, because the constructor of the Foo class can propagate an exception from the MyParser class:

public Foo(String row) throws Exception {
        String split[] = StringUtils.split(row, "Ú");
        field    =   MyParser.getInt(split[0]);
}

Is it possible to use the Java stream API anyway? Maybe with only one awesome stream? Somethings like this:

stream.map(Foo::new).forEach(foo -> fooRepository.save(foo));

I use Java 8 with Spring Boot 1.5.8.

Upvotes: 1

Views: 76

Answers (1)

Eugene
Eugene

Reputation: 120978

If you can edit the class, why not simply throw a RuntimeException instead of throwing an Exception. If the API that you use still throws Exception you can just wrap it into:

catch(Exception e){
    throw new RuntimeException(e);
}

Then you can simplify it to :

 stream.map(Foo::new).forEach(fooRepository::save)

Upvotes: 4

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