Programmer Think

1, Foreword How to learn if you can't use it? Without scenes and demands, it seems that there is no need to learn these knowledge points. In fact, the best way is to summarize, sort out, practice and output. After a set of combination boxing, you will master this series of knowledge. However, it may not be used at the current stage. The ...

set password for 'user name'@'IP address' = Password('New password'); Note: the data related to user permissions are saved in the user table of mysql database, so you can also operate them directly (not recommended) I'm tired after watching for so long. Take a break for 10 seconds and continue to look down 4, Authority management mysql h ...

3. Alibaba code specification stipulates that methods and attributes in the interface should not be decorated with any symbols to keep the code concise Implement multiple interfaces Sometimes we need to make a class inherit from multiple parent classes at the same time This is achieved in some programming languages through multiple inherita ...

Spring social introduced in previous blogs encapsulates third-party applications, goes to service providers and obtains user information through OAuth protocol. Here we need to complete the logic development of the service provider, so we need to use spring security OAuth Using spring security OAuth, we can quickly build the logic of the ser ...

* Static inner class. be used for hash Operation! */ public static class SimpleHash { private int cap; private int seed; public SimpleHash(int cap, int seed) { this.cap = cap; this.seed = seed; } /** * Calculate hash value */ public int hash(Object value) { int h; return (value == null) ? 0 : Math.abs(seed * (c ...

In the Incremental mode l, each collection process is paused twice, and the second time is slightly longer. For the first time, simply query the surviving object from root. The second time it is used to examine the survivors in detail. The whole process is as follows: * stop all application threads; do the initial mark; resume all application ...

Time complexity mainly measures the running speed of an algorithm, while space complexity mainly measures the additional space required by an algorithm. In the early days of computer development, the storage capacity of computer was very small. So I care about the complexity of space. However, with the rapid development of computer industry, ...

Stream It is used to perform various operations and operations on the data in the collection, such as filtering, sorting, mapping... Finally get the result The collection focuses on the storage of data, and the Stream stream focuses on the operation and operation of the data stored in the collection Use steps Gets the object of a Stream s ...

It mainly acts on the DAO interface and can automatically generate the implementation class of the interface. 8: @MapperScan It is mainly used on the startup class to generate the implementation class of DAO interface. If there are many DAO interfaces, it is recommended to use @ MapperScan annotation, such as @ MapperScan("com.example. ...

The following is an example of parsing a string, which you can refer to: public static void main(String[] args) throws Exception { //Parses the given String text into an XML document and returns the newly created document org.dom4j.Document document = DocumentHelper.parseText(xmlString); //Get the root node, in thi ...