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Updating readme file

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Gunnar Morling 2013-04-07 17:07:56 +03:00
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@ -4,7 +4,7 @@ MapStruct is a Java [annotation processor](http://docs.oracle.com/javase/6/docs/
All you have to do is to define a mapper interfaces, annotate it with the `@Mapper` annotation and add the required mapping methods. During compilation, MapStruct will generate an implementation for the mapper interface. This implementation uses plain Java method invocations, i.e. no reflection or similar.
## Hello World
# Hello World
The following shows a simple example for using MapStruct. First, let's define an object (e.g. a JPA entity) and an accompanying data transfer object (DTO):
@ -64,36 +64,32 @@ public void shouldMapCarToDto() {
}
```
Sometimes not only the names of two corresponding attributes differ, but also their types. This can be addressed by defining a custom type converter:
# Advanced mappings
public class IntToStringConverter implements Converter<Integer, String> {
## Reverse mappings
@Override
public String from(Integer source) {
return source != null ? source.toString() : null;
}
Often bi-directional mappings are required, e.g. from entity to DTO and from DTO to entity. For this purpose, simply declare a method with the required parameter and return type on the mapping interface which also declares the forward mapping method:
@Override
public Integer to(String target) {
return target != null ? Integer.valueOf( target ) : null;
}
}
To make use of a converter, specify its type within the `@Mapping` annotation:
@Mapper
public interface CarMapper {
```java
@Mapper
public interface CarMapper {
CarMapper INSTANCE = Mappers.getMapper( CarMapper.class );
@Mappings({
@Mapping(source = "numberOfSeats", target = "seatCount"),
@Mapping(source = "yearOfManufacture", target = "manufacturingYear", converter = IntToStringConverter.class)
})
@Mapping(source = "numberOfSeats", target = "seatCount")
CarDto carToCarDto(Car car);
Car carDtoToCar(CarDto carDto);
}
Car carDtoToCar(CarDto carDto); (1)
}
```
1. The `carDtoToCar()` method is the reverse mapping method for `carToCarDto()`. Note that the attribute mappings only have to be specified at one of the two methods and will be applied to the corresponding reverse mapping method as well.
## Mapping referenced objects and collections
Typically an object has not only primitive attributes but also references other objects. E.g. the `Car` class could contain a reference to a `Driver` object, while the `CarDto` class references a `DriverDto` object.
TODO
# Using MapStruct
@ -107,9 +103,7 @@ For Maven based projects add the following to your POM file in order to use MapS
<org.mapstruct.version>[current MapStruct version]</org.mapstruct.version>
</properties>
<!-- ... -->
...
<dependencies>
<dependency>
<groupId>org.mapstruct</groupId>
@ -117,9 +111,7 @@ For Maven based projects add the following to your POM file in order to use MapS
<version>${org.mapstruct.version}</version>
</dependency>
</dependencies>
<!-- ... -->
...
<build>
<plugins>
<plugin>