如何在YAML中将Java字符串解析为文字块

Question

I need to parse only the Java Strings description , instructions as literal blocks ( | ) in yaml,as both the above variables can contain multiline inputs and parse infoId as a usual string. I am using snakeyaml as the yaml library. How do I achieve the above? Is there any annotation that I need use for this?

Pojo class

public class Info {

private String infoId;
private String description;
private String instructions;

// Setters and getters
}

parsing class

...
Info info = new Info();
info.setDescription(descriptionWithMultilines);
info.setIntructions(instructionsWithMultilines);

Yaml yaml = new Yaml();
String yamlString = yaml.dumpAs(info, Tag.MAP, DumperOptions.FlowStyle.BLOCK);
...

Answer 1

If you want to exclude specific properties you can achieve it by using a custom Representer class

this short snippet

public static void main(String[] args) {
    Info info = new Info();
    info.setInfoId("demo");
    info.setDescription("foo\nbar");
    info.setInstructions("one\ntwo");

    Yaml yaml = new Yaml(new InfoRepresenter());
    String yamlString = yaml.dumpAs(info, Tag.MAP, DumperOptions.FlowStyle.BLOCK);
    System.out.println(yamlString);
}

private static class InfoRepresenter extends Representer {
    @Override
    protected NodeTuple representJavaBeanProperty(Object javaBean, Property property, Object propertyValue,
            Tag customTag) {
        if (javaBean instanceof Info && "infoId".equals(property.getName())) {
            return null;
        } else {
            return super.representJavaBeanProperty(javaBean, property, propertyValue,
                    customTag);
        }
    }
}

produces following output

description: |-
  foo
  bar
instructions: |-
  one
  two