Kotlin Stdlib Common technical analysis and JAVA class library integration reality
KOTLIN's Stdlib Common is a library used to achieve cross -platform development. It allows developers to write shared code in the Kotlin language and use them on different platforms, such as Android, iOS, and Web applications.This article will analyze Kotlin's Stdlib Common technical principles and introduces how to integrate it with the Java library.
Kotlin's Stdlib Common technical principles are mainly based on the Kotlin multi -platform project (KMP).KMP provides a solution to share code on different platforms, including cross -platform support of the Kotlin language itself and some specific tools and frameworks.Stdlib Common is part of KMP, which provides a set of general standard library functions and classes that can be used on different platforms.
By using KMP and STDLIB Common, developers can write a code in Kotlin and then use it in applications of different platforms.Developers can define universal functions, classes, and interfaces, and use Expect and Actual keywords to implement different platforms.Expect keywords are used to define universal declarations, and the Actual keywords are used to specify the specific implementation of different platforms.
Next, we will introduce a practical example to show how to integrate Kotlin's Stdlib Common and Java libraries.
Suppose we have a Kotlin multi -platform project, we need to use JSON serialization and dependentization functions in Android applications and Java Web applications.We can use Kotlin's Stdlib Common to implement this function.
First of all, we can define a universal interface in Kotlin to declare the function of JSON serialization and desertileization:
kotlin
expect interface JsonConverter<T> {
fun toJson(obj: T): String
fun fromJson(json: String): T
}
Next, we need to implement this interface in Android applications.In the code of the Android module, we can use the GSON library to implement JSON serialization and back -serialization function:
kotlin
actual class AndroidJsonConverter<T> : JsonConverter<T> {
private val gson = Gson()
actual override fun toJson(obj: T): String {
return gson.toJson(obj)
}
actual override fun fromJson(json: String): T {
return gson.fromJson(json, object : TypeToken<T>() {}.type)
}
}
We need to implement this interface in the Java Web application.In the Java code, we can use the Jackson library to implement JSON's serialization and back -sequentialization function:
public class JavaWebJsonConverter<T> implements JsonConverter<T> {
private final ObjectMapper objectMapper = new ObjectMapper();
public String toJson(T obj) {
try {
return objectMapper.writeValueAsString(obj);
} catch (JsonProcessingException e) {
e.printStackTrace();
return "";
}
}
public T fromJson(String json) {
try {
return objectMapper.readValue(json, new TypeReference<T>() {});
} catch (IOException e) {
e.printStackTrace();
return null;
}
}
}
Finally, in Android applications and Java Web applications, we can use these implementation classes to perform JSON serialization and derivative operation:
kotlin
val jsonConverter: JsonConverter<User> = if (isAndroid()) {
AndroidJsonConverter()
} else {
JavaWebJsonConverter()
}
val userJson = jsonConverter.toJson(user)
val user = jsonConverter.fromJson(userJson)
By using Kotlin's Stdlib Common and Java class libraries, we can write it in the Kotlin code once, and then reuse these code on different platforms to achieve cross -platform development.
Summarize:
This article introduces Kotlin's Stdlib Common technical principles and provides an example to show how to integrate Kotlin's Stdlib Commod and Java libraries.By using Kotlin's Stdlib Common, developers can share code on different platforms to achieve cross -platform development.At the same time, through the specific implementation of different platforms, it can be integrated with the Java class library to provide richer functions and support.
