Java Model Converter

This utility library helps to convert from one POJO to another using public getters and setters via reflection mechanism.

Table of contents

• Getting started
  • Maven
  • Gradle
• Usage
  • Non-parameterized classes
  • Parameterized classes
• Adding custom converters
• Adding custom mappings
• License

Getting started

To add library to your project perform next steps:

Maven

Add the following dependency to your pom.xml:

<dependency>
      <groupId>com.github.vladislavsevruk</groupId>
      <artifactId>model-converter</artifactId>
      <version>1.0.2</version>
</dependency>

Gradle

Add the following dependency to your build.gradle:

implementation 'com.github.vladislavsevruk:model-converter:1.0.2'

Usage

ModelConverter uses POJO's getters and setters with matching names to get and set values from one POJO to another. Getters and setters name can be in both classic and fluent styles, e.g. getter with name getField can match setters with setField or field names (same setter with name setField can match getters with getField or field names). If return type of getter doesn't match parameter type of setter it'll be converted to required type if any of predefined converters can perform such conversion. You can add your custom converter if you want to set custom conversion logic or override logic of existent one.

Non-parameterized classes

Let's assume that we have following POJO:

public class DonorModel {
    private Set<String> field1;
    private Integer field2;

    // getters and setters
}

and we want to convert it to following POJO:

public class AcceptorModel {
    private List<String> field1;
    private String field2;

    // getters and setters
}

All you have to do is to use ModelConverter.convert(Object, Class<T>) method:

// creating POJO with values to convert
DonorModel donorModel = new DonorModel();
donorModel.setField1(Collections.singleton("specificValue"));
donorModel.setField2(2);
// converting POJO to another one
AcceptorModel acceptorModel = new ModelConverter().convert(donorModel, AcceptorModel.class);
// verifying field values
Assertions.assertEquals(1, acceptorModel.getField1().size());
Assertions.assertEquals("specificValue", acceptorModel.getField1().get(0));
Assertions.assertEquals("2", acceptorModel.getField2());

Parameterized classes

Let's assume that we have following generic POJO:

public class GenericDonorModel<T> {

    private Set<String> field1;
    private T field2;

    // getters and setters
}

and we want to convert it to following generic POJO:

public class GenericAcceptorModel<T> {

    private List<String> field1;
    private T field2;

    // getters and setters
}

All you have to do is to use ModelConverter.convert(Object, TypeProvider<T>) method:

// creating POJO with values to convert
GenericDonorModel<Integer> donorModel = new GenericDonorModel<>();
donorModel.setField1(Collections.singleton("specificValue"));
donorModel.setField2(2);
// converting POJO to another one
GenericAcceptorModel<String> acceptorModel = new ModelConverter()
        .convert(donorModel, new TypeProvider<GenericAcceptorModel<String>>() {});
// verifying field values
Assertions.assertEquals(1, acceptorModel.getField1().size());
Assertions.assertEquals("specificValue", acceptorModel.getField1().get(0));
Assertions.assertEquals("2", acceptorModel.getField2());

Adding custom converters

If you want to set custom conversion logic for any type or override logic of existent one you can implement ClassTypeConverter for non-parameterized type or ParameterizedTypeConverter for parameterized type and add it to TypeConverterStorage using one of add* methods:

ConversionContextManager.getContext().getTypeConverterStorage().add(new SomeCustomTypeConverter());

Adding custom mappings

By default converter matches donor and acceptor methods that have same names (in classic or fluent styles) but you can add custom mapping to CustomGetterSetterMappingStorage to point getter to certain setter using one of addGetterSetterMapping methods (necessary converter will still be added if necessary):

public class DonorModel {
    private String donorField1;
    private Integer donorField2;

    // getters and setters
}

public class AcceptorModel {
    private String acceptorField;

    // getters and setters
}

Method donorMethod = DonorModel.class.getMethod("getDonorField1");
Method acceptorMethod = AcceptorModel.class.getMethod("setAcceptorField", String.class);
ConversionContextManager.getContext().getCustomGetterSetterMappingStorage()
        .addGetterSetterMapping(donorMethod, acceptorMethod);

License

This project is licensed under the MIT License, you can read the full text here.