org.robolectric.config.ConfigurationRegistry Maven / Gradle / Ivy
Show all versions of shadowapi Show documentation
package org.robolectric.config;
import java.io.ByteArrayInputStream;
import java.io.ByteArrayOutputStream;
import java.io.IOException;
import java.io.ObjectInputStream;
import java.io.ObjectOutputStream;
import java.util.HashMap;
import java.util.Map;
/**
* Holds configuration objects for the current test, computed using {@link Configurer}.
*
* Configuration is computed before tests run, outside of their sandboxes. If the configuration
* is needed from within a sandbox (when a test is executing), we need to transfer it to a class
* that the SandboxClassLoader recognizes. We do this by serializing and deserializing in {@link
* #maybeReloadInSandboxClassLoader(Object)}.
*/
public class ConfigurationRegistry {
public static ConfigurationRegistry instance;
/** Returns the configuration object of the specified class, computed using {@link Configurer}. */
public static T get(Class configClass) {
return instance.getInSandboxClassLoader(configClass);
}
private final Map configurations = new HashMap<>();
public ConfigurationRegistry(Map, Object> configClassMap) {
for (Class classInParentLoader : configClassMap.keySet()) {
Object configInParentLoader = configClassMap.get(classInParentLoader);
configurations.put(classInParentLoader.getName(), configInParentLoader);
}
}
private T getInSandboxClassLoader(Class someConfigClass) {
Object configInParentLoader = configurations.get(someConfigClass.getName());
if (configInParentLoader == null) {
return null;
}
Object configInSandboxLoader = maybeReloadInSandboxClassLoader(configInParentLoader);
return someConfigClass.cast(configInSandboxLoader);
}
/**
* Reloads the value of the config in the current class loader. This has to be done in case of
* custom {@link org.robolectric.pluginapi.config.Configurer} classes. If there is a custom
* Configurer class, the config value will be initialized in the Application ClassLoader, before
* any tests are run. However, because custom config classes will typically not be included in
* {@link AndroidConfigurer}, they will be acquired by the Robolectric ClassLoader and redefined
* whenever they are referenced during the lifecycle of a Robolectric test. This causes a problem
* because an object of ConfigClass[ApplicationClassLoader] cannot be cast to a
* ConfigClass[RobolectricClassLoader].
*
* Note this logic is not required for built-in Config classes because there are rules in
* {@link AndroidConfigurer} to exclude org.robolectric.annotation.* classes from being acquired
* by Robolectric ClassLoaders.
*/
@SuppressWarnings("BanSerializableRead")
private static Object maybeReloadInSandboxClassLoader(Object configInParentLoader) {
// Avoid reloading for built-in config from the org.robolectric.annotation package. This package
// is excluded from instrumentation, so it will always exist in the Application ClassLoader.
if (configInParentLoader.getClass().getName().startsWith("org.robolectric.annotation.")) {
return configInParentLoader;
}
ByteArrayOutputStream buf = new ByteArrayOutputStream();
try (ObjectOutputStream out = new ObjectOutputStream(buf)) {
out.writeObject(configInParentLoader);
} catch (IOException e) {
throw new RuntimeException(e);
}
byte[] bytes = buf.toByteArray();
// ObjectInputStream loads classes in the current classloader by magic
try (ObjectInputStream in = new ObjectInputStream(new ByteArrayInputStream(bytes))) {
return in.readObject();
} catch (IOException | ClassNotFoundException e) {
throw new RuntimeException(e);
}
}
}