Programmer Group

Android 4.4 Publish ART virtual machine and provide options to enable it.The underlying implementation of HttpURLConnection is changed to OkHttp. Android 5.0 ART becomes the default virtual machine and completely replaces Dalvik virtual machine.The Context.bindService() method requires an explicit intent. If an implicit intent is provided, an ...

Chapter 17 Java 8 new features primary coverage Lambda expressionStreamAPIOptional Learning objectives Be able to understand the advantages of functional programming over object-oriented programming Be able to master the standard format of Lambda expression Ability to use Lambda standard format Be able to master the ellipsis format and rul ...

1, Concept 1.1,TLS Transport Layer Security protocol As the successor of SSL protocol, it has become the next generation network security and data integrity security protocol 1.2,SSL Secure Socket Layer The network transport layer, located in TCP/IP, is a security protocol that provides security and data integrity for network communication ...

1. Object class 1.1. equals method 1.1.1 comparison of = = and equals ==Is a comparison operator ==: you can judge both the basic type and the reference type ==: if the basic type is judged, whether the values are equal is judged ==: if the reference type is judged, whether the addresses are equal is judged, that is, whether the same ...

Java 13 Officially released on September 17, 2019, please Download Java 13 here. Some new features in Java 13 JEP 350: dynamic CDS Archive JEP-351: ZGC: uncommit unused memory JEP-353: re implementing legacy socket API JEP-354: switch expression (Preview) (developer function) JEP-355: text block (Preview) (developer function) 1. JEP 350 dyn ...

DataX is Alibaba's heterogeneous data source offline synchronization tool. For detailed introduction and use, please refer to Introduction to the official website and Quick Start . DataX series mainly introduces the principle of the whole operation in more detail.ConfigurationThe parsing of DataX configuration includes three files: job.json, c ...

Open Closed Principle (OCP): when the application requirements change, the functions of the module can be extended to meet the new requirements without modifying the source code or binary code of the software entity.Liskov Substitution Principle (LSP): subclasses can extend the functions of the parent class, but cannot change the original funct ...

1, Message queue 1.1 related concepts of MQ 1.1.1 what is MQ MQ(message queue), in its literal sense, is essentially a queue. FIFO is first in, first out, but the contents stored in the queue are messages. It is also a cross process communication mechanism for upstream and downstream message delivery. In the Internet architecture, MQ is ...

When we do projects, we often need to integrate and filter the data, and judge after using the for loop every time. I believe you must be tired. Now the Lamda expression newly exited by Java 8 and Steam API can perfectly process the data and complete the function of shuttling between the data. Stream means stream, which is slightly differen ...

GUI-AWT event handling The introduction of event handling mechanism is to respond to the user's behavior. Previously, after creating the Frame window, click X, but it cannot be closed. Because in AWT, all events must be handled by a specific object (event listener), the Frame and component itself are just a framework and cannot respond. Loading ...