Hello, Type Systems! - Introduction to Featherweight Javay_taka_23
?
This document introduces Featherweight Java (FJ), a formalized minimal model of Java. FJ focuses on expressions, typing rules, and reduction rules. Expressions include variables, constructors, field access, method invocation and casts. Typing rules determine if an expression has a valid type in a given environment. Reduction rules define how expressions are evaluated or "reduced". Type safety in FJ means that a well-typed expression will reduce to a constructor-only expression without getting stuck.
Hello, Type Systems! - Introduction to Featherweight Javay_taka_23
?
This document introduces Featherweight Java (FJ), a formalized minimal model of Java. FJ focuses on expressions, typing rules, and reduction rules. Expressions include variables, constructors, field access, method invocation and casts. Typing rules determine if an expression has a valid type in a given environment. Reduction rules define how expressions are evaluated or "reduced". Type safety in FJ means that a well-typed expression will reduce to a constructor-only expression without getting stuck.
The document summarizes Linux scheduling in 3 key points:
1. Tasks can be in one of several states like RUNNING, INTERRUPTIBLE, STOPPED.
2. Runnable tasks are organized by priority in active and expired priority arrays. The task with highest priority in the active array runs.
3. When a task's time slice expires, it moves to the expired array and the next highest priority task in the active array runs. Bitmaps and queues track tasks between the arrays.
This document introduces Retrofit, an Android library for making REST API calls. It discusses how to define API interfaces, generate implementations, and make requests. Key features covered include defining endpoints as methods, using interfaces as API specifications, asynchronous requests with callbacks, support for different data format converters, and setting static and dynamic header values. The conclusion states that Retrofit provides a way to avoid issues with incorrect or outdated API documentation.
The document summarizes the key features and highlights of Spring Boot 1.3, which is scheduled for release in September 2015. Some of the main things covered include Spring 4.2 support, new auto-configurations for caching, OAuth2, and other components, improvements to non-functional aspects like metrics export, and enhancements to DevOps tools including a systemd service generator and improved development tools. Upcoming user group events related to Spring are also announced.
13. 以下のコードをコンパイル、実行した時
の結果として正しいものを選びなさい。
public class Example {
public static void main(String[] args) {
Thread t = new Thread(new Runnable(){
public void run(){
System.out.println("running");
}
});
t.start();
t.start();
}
}
A. 正常に実行され、?running?が表示される
B. 正常に実行され、?runningrunning?が表示される
C. コンパイルエラーになる
D. 実行時に例外がスローされる
14. 以下のコードをコンパイル、実行した時
の結果として正しいものを選びなさい。
public class Example {
public static void main(String[] args) {
Thread t = new Thread(new Runnable(){
public void run(){
System.out.println("running");
}
});
t.start();
t.start();
}
}
A. 正常に実行され、?running?が表示される
B. 正常に実行され、?runningrunning?が表示される
C. コンパイルエラーになる
D. 実行時に例外がスローされる IllegalThreadStateException