Allow registration of a Supplier of Randomizers #28

random-beans/src/main/java/io/github/benas/randombeans/EnhancedRandomBuilder.java

@@ -31,6 +31,7 @@
 import io.github.benas.randombeans.randomizers.registry.CustomRandomizerRegistry;
 
 import java.util.*;
+import java.util.function.Supplier;
 
 import static io.github.benas.randombeans.util.Constants.DEFAULT_SEED;
 
@@ -77,6 +78,18 @@ public <T, F, R> EnhancedRandomBuilder randomize(FieldDefinition<T, F> fieldDefi
  return this;
  }
 
+ /**
+ * Register a {@code Supplier} of custom {@link Randomizer}s for a given field.
+ *
+ * @param fieldDefinition definition of the field to randomize
+ * @param randomizerSupplier the custom Supplier of {@link Randomizer}s to use
+ * @return a pre configured {@link EnhancedRandomBuilder} instance
+ */
+ public <T, F, R> EnhancedRandomBuilder randomize(FieldDefinition<T, F> fieldDefinition, Supplier<Randomizer<R>> randomizerSupplier) {
+ customRandomizerRegistry.registerRandomizerSupplier(fieldDefinition.getName(), fieldDefinition.getType(), fieldDefinition.getClazz(), randomizerSupplier);
+ return this;
+ }
+
  /**
  * Exclude a field from being populated.
  *

random-beans/src/main/java/io/github/benas/randombeans/randomizers/registry/CustomRandomizerRegistry.java

@@ -32,6 +32,7 @@
 import java.lang.reflect.Field;
 import java.util.HashMap;
 import java.util.Map;
+import java.util.function.Supplier;
 
 /**
  * Registry of user defined randomizers.
@@ -42,6 +43,7 @@
 public class CustomRandomizerRegistry implements RandomizerRegistry {
 
  private Map<FieldDefinition<?, ?>, Randomizer<?>> customRandomizersRegistry = new HashMap<>();
+ private Map<FieldDefinition<?, ?>, Supplier<?>> customRandomizersSupplierRegistry = new HashMap<>();
 
  /**
  * Set the initial seed for all randomizers of the registry
@@ -55,7 +57,13 @@ public void setSeed(long seed) {
 
  @Override
  public Randomizer<?> getRandomizer(Field field) {
- return customRandomizersRegistry.get(new FieldDefinition<>(field.getName(), field.getType(), field.getDeclaringClass()));
+ FieldDefinition<?, ?> fieldDefinition = new FieldDefinition<>(field.getName(), field.getType(), field.getDeclaringClass());
+ @SuppressWarnings("unchecked")
+ Supplier<Randomizer<?>> randomizerSupplier = (Supplier<Randomizer<?>>) customRandomizersSupplierRegistry.get(fieldDefinition);
+ if (randomizerSupplier != null) {
+ return randomizerSupplier.get();
+ }
+ return customRandomizersRegistry.get(fieldDefinition);
  }
 
  @Override
@@ -67,4 +75,8 @@ public <T, F, R> void registerRandomizer(final String fieldName, final Class<F>
  customRandomizersRegistry.put(new FieldDefinition<>(fieldName, fieldType, type), randomizer);
  }
 
+ public <T, F, R> void registerRandomizerSupplier(final String fieldName, final Class<F> fieldType, final Class<T> type, final Supplier<Randomizer<R>> randomizerSupplier) {
+ customRandomizersSupplierRegistry.put(new FieldDefinition<>(fieldName, fieldType, type), randomizerSupplier);
+ }
+
 }

random-beans/src/test/java/io/github/benas/randombeans/EnhancedRandomImplTest.java

@@ -28,6 +28,8 @@
 import io.github.benas.randombeans.api.ObjectGenerationException;
 import io.github.benas.randombeans.api.Randomizer;
 import io.github.benas.randombeans.beans.*;
+import io.github.benas.randombeans.randomizers.ConstantRandomizer;
+
 import org.junit.Before;
 import org.junit.Test;
 import org.junit.runner.RunWith;
@@ -36,6 +38,7 @@
 
 import java.util.Date;
 import java.util.List;
+import java.util.function.Supplier;
 
 import static io.github.benas.randombeans.EnhancedRandomBuilder.aNewEnhancedRandomBuilder;
 import static io.github.benas.randombeans.FieldDefinitionBuilder.field;
@@ -132,6 +135,49 @@ public void generatedBeansWithCustomRandomizersShouldBeCorrectlyPopulated() {
  assertThat(person.getName()).isEqualTo(NAME);
  }
 
+ @Test
+ public void generatedBeansWithCustomRandomizerSupplierShouldBeCorrectlyPopulated() {
+ FieldDefinition<?, ?> nameFieldDefinition = field().named("name").ofType(String.class).inClass(Human.class).get();
+ enhancedRandom = aNewEnhancedRandomBuilder().randomize(nameFieldDefinition, new Supplier<Randomizer<String>>() {
+ private boolean firstCall = true;
+
+ public Randomizer<String> get() {
+ if (firstCall) {
+ firstCall = false;
+ return new ConstantRandomizer<String>(NAME);
+ }
+ return new ConstantRandomizer<String>(NAME + NAME);
+ }
+ }).build();
+
+ Human firstHuman = enhancedRandom.nextObject(Human.class);
+
+ assertThat(firstHuman).isNotNull();
+ assertThat(firstHuman.getName()).isEqualTo(NAME);
+
+ Person secondHuman = enhancedRandom.nextObject(Person.class);
+
+ assertThat(secondHuman).isNotNull();
+ assertThat(secondHuman.getName()).isEqualTo(NAME + NAME);
+ }
+
+ @Test
+ public void customRandomizerSupplierShouldHavePrecedenceOverCustomRandomizer() {
+ FieldDefinition<?, ?> nameFieldDefinition = field().named("name").ofType(String.class).inClass(Human.class).get();
+ enhancedRandom = aNewEnhancedRandomBuilder()
+ .randomize(nameFieldDefinition, new Supplier<Randomizer<String>>() {
+ public Randomizer<String> get() {
+ return new ConstantRandomizer<String>(NAME);
+ }
+ })
+ .randomize(nameFieldDefinition, new ConstantRandomizer<String>("abc")).build();
+
+ Human firstHuman = enhancedRandom.nextObject(Human.class);
+
+ assertThat(firstHuman).isNotNull();
+ assertThat(firstHuman.getName()).isEqualTo(NAME);
+ }
+
  @Test
  public void javaNetTypesShouldBePopulated() {