io.hyperfoil.api.config.BuilderBase Maven / Gradle / Ivy
package io.hyperfoil.api.config;
import java.lang.annotation.ElementType;
import java.lang.annotation.Retention;
import java.lang.annotation.RetentionPolicy;
import java.lang.annotation.Target;
import java.lang.reflect.Constructor;
import java.lang.reflect.Field;
import java.lang.reflect.Modifier;
import java.util.Arrays;
import java.util.Collection;
import java.util.List;
import java.util.Map;
/**
* Intended base for all builders that might need relocation when the step is copied over.
*/
public interface BuilderBase> {
default void prepareBuild() {
Class clz = getClass();
while (clz != null && clz != Object.class) {
for (Field f : clz.getDeclaredFields()) {
if (f.isSynthetic() || Modifier.isStatic(f.getModifiers()) || "parent".equals(f.getName())) {
continue;
}
f.setAccessible(true);
try {
tryPrepare(clz, f.getName(), f.getType(), f.get(this));
} catch (IllegalAccessException e) {
throw new UnsupportedOperationException(
"Cannot get value of " + clz.getName() + "." + f.getName() + " (actual instance: " + this + ")");
}
}
clz = clz.getSuperclass();
}
}
private void tryPrepare(Class clz, String name, Class type, Object value) throws IllegalAccessException {
if (BuilderBase.class.isAssignableFrom(type)) {
if (value != null) {
((BuilderBase) value).prepareBuild();
}
} else if (Collection.class.isAssignableFrom(type)) {
if (value != null) {
for (Object item : (Collection) value) {
if (item != null) {
tryPrepare(clz, name, item.getClass(), item);
}
}
}
} else if (BaseSequenceBuilder.class.isAssignableFrom(type)) {
if (value != null) {
((BaseSequenceBuilder) value).prepareBuild();
}
} else if (Map.class.isAssignableFrom(type)) {
if (value != null) {
for (Map.Entry entry : ((Map) value).entrySet()) {
if (entry.getKey() != null) {
tryPrepare(clz, name, entry.getKey().getClass(), entry.getKey());
}
if (entry.getValue() != null) {
tryPrepare(clz, name, entry.getValue().getClass(), entry.getValue());
}
}
}
} else if (type.isArray()) {
throw new UnsupportedOperationException(clz.getName() + "." + name + " is an array (actual instance: " + this + ")");
}
}
/**
* Some scenarios copy its parts from one place to another, either during parsing
* phase (e.g. through YAML anchors) or in {@link #prepareBuild()}.
* In order to make sure that modification in one place does not accidentally change
* the original one we require defining a deep copy method on each builder. The only
* exception is when the builder is immutable (including potential children builder);
* in that case the deep copy is not necessary and this method can return this.
*
* The default implementation uses reflection to create a deep copy of all collections and maps,
* calling copy() on all objects implementing {@link BuilderBase}.
*
* @param newParent Object passed to a matching constructor.
* @return Deep copy of this object.
*/
@SuppressWarnings("unchecked")
default S copy(Object newParent) {
if (getClass().isSynthetic()) {
// This is most likely a lambda supplier of the instance (which should be immutable anyway)
assert getClass().getSimpleName().contains("$$Lambda$");
return (S) this;
}
try {
ThrowingSupplier> constructor = null;
for (Constructor ctor : getClass().getConstructors()) {
// parameterless constructor has lowest priority
if (ctor.getParameterCount() == 0 && constructor == null) {
constructor = () -> (BuilderBase) ctor.newInstance();
} else if (ctor.getParameterCount() == 1) {
Class parameterType = ctor.getParameterTypes()[0];
if (parameterType == getClass()) {
constructor = () -> (BuilderBase) ctor.newInstance(this);
// copy constructor has highest priority
break;
} else if (newParent != null && parameterType.isAssignableFrom(newParent.getClass())) {
constructor = () -> (BuilderBase) ctor.newInstance(newParent);
}
}
}
if (constructor == null) {
throw new NoSuchMethodException("No constructor for " + getClass().getName());
}
BuilderBase copy = constructor.get();
Class cls = getClass();
while (cls != null && cls != BuilderBase.class) {
for (Field f : cls.getDeclaredFields()) {
f.setAccessible(true);
if (Modifier.isStatic(f.getModifiers())) {
// do not copy static fields
} else if (f.isAnnotationPresent(IgnoreCopy.class)) {
// field is intentionally omitted
} else if (Modifier.isFinal(f.getModifiers())) {
Object thisValue = f.get(this);
Object copyValue = f.get(copy);
if (thisValue == copyValue) {
// usually happens when the value is null
} else if (copyValue instanceof Collection) {
// final collections can only get the elements
Collection