Conversions

Getting started with Mapper.apex

During the mapping, we can also transform the values.

Mapper m = new Mapper()
    .mapField('name', 'Name', R.prepend.apply('Mr. '))
    .toMap();
Map data = (Map)m.run(acc);
// Create a map containing 'name' with the value prepended with 'Mr. '

In this example, we transform the value of 'Name' by prepending 'Mr. ', and then set it to field 'name'.

We can go further than simply one field. Converting value from multiple fields is also supported.

Mapper m = new Mapper()
    .mapField('desc', 'Name', 'Description', R.concat)
    .toMap();
Map data = (Map)m.run(acc);
// Create a map containing 'desc' with the value of 'Name'
// and 'Description' values concatenated

Here we concatenate the values of 'Name' and 'Description' and then set it to the field 'desc'.

Besides, we can easily access values in nested fields.

Mapper m = new Mapper()
    .mapField('person.name', 'Account.Name')
    .toMap();
Map data = (Map)m.run(src);
// Create a map with nested maps, 'person => name' with the value
// of 'Account => Name' from the source map

We get the value from nested fields 'Account.Name' and then set it to a nested field 'person.name'.

The hidden power is that we can even convert multiple objects into one.

Mapper m = new Mapper()
    .inputAs('src1', 'src2')
    .mapField('name', 'src1.Name')
    .mapField('desc', 'src2.Description')
    .toMap();
Map data = (Map)m.run(src1, src2);
// Create a map containing 'name' and 'desc' with values
// from two source objects

In this example, we convert from src1 and src2 into data, by picking Name of src1 and Description of src2.

Done