Java

Background: Deploy two projects at the same time as Tomcat, launch java.lang.OutOfMemoryError: PermGen spaceCause: Because there are too many jar packages for two items, the JVM explodes the default memory when loading the class file.Workaround:(1)

A script that runs Appium today encounters this problem:java.lang.unsupportedclassversionerror:io/appium/java_client/appiumdriver:unsupported Major.minor Version51.0At Java.lang.ClassLoader.defineClass1 (Native Method) at

Behavior of the object1. Breakpoint DebuggingA: Positioning (setting breakpoints)B: Start debuggingC: Stepping through the observation variable (F5 stepping F6 Single Step)D: Modify2 static StaticsStatic members, which are shared in static methods

Java.lang.IllegalStateException This exception, does not mean that the file cannot be downloaded, does not mean that the program is written incorrectly, it will continue to run normally after Tomcat throws an exception. Just look at the

3 Kinds of sortingTreeSet : Sort: You must implement the java.lang.Comparable interface in the class to which the object belongs, and override the Tocompare () method.List + Collection Tool class: Collections.sort (list): You need to

Java Study Notes-HttpServletResponse (22), java Study Notes 1. garbled Processing A GET request is a request that uses the get data submitted directly through a carriage return or hyperlink click in the address bar and the method in the form. Is the

Springmvc + mybatis + spring configuration, spring things, springmvcmybatis After being configured for half a day today, we found that things are ineffective and the following error occurs: org.mybatis.spring.transaction.SpringManagedTransaction] - [

Bean machine/plum blossom bottle java, plum blossom bottle java 1 import java. util. *; 2 3 public class Slots6_21 {4 final static int DEPTH = 10; 5 6 public static void main (String [] args) {7 rows input = new rows (System. in); 8 9 System. out.

Sshe source code analysis-global architecture, sshe source code global   In Web. xml sessionFilter sy. util. base. SessionFilter include securityJsp sessionFilter *. jsp If the sessionFilter listening URL contains the included

Hibernate4.3.8 problems encountered during the integration of struts2, struts2 integrates hibernate 1. Exceptions: Exception in thread "main" org. hibernate. service. spi. ServiceException: Unable to create requested service [org. hibernate. cache.

Analysis of JAVA design mode (2)2. rys replacement Principle: the LSP (Liskov Substitution Principle) Rys replacement Principle is defined as long as the Child class appears in the parent class, and after the child class is replaced, the program

Improve development efficiency and Efficiency 1. Clarify the software Objectives 2 term-entity, and the relationship between each entity, and draw a E-R diagram. (It is best to create a document at the beginning of the project) 3. A stable

Lintcode: Rehashing, lintcoderehashing The size of the hash table is not determinate at the very beginning. If the total size of keys is too large (e.g. size >= capacity / 10), we should double the size of the hash table and rehash every keys. Say

[Switch] Hibernate and ibatis comparison, hibernateibatis 1. Introduction Hibernate is currently the most popular O/R mapping Framework. It was born in sf.net and has become a part of Jboss. IBATIS is another excellent O/R mapping Framework, which

JAVA multithreading mechanism (I), java multithreading mechanism PS: I started to talk about JAVA again .. Some time ago, I completed HTML + CSS. It was boring to start writing the lab interface... The blog will be updated later! Update JAVA first...

Spring Learning (2) common Spring annotations Common Spring annotations Construct an IoC Container Using annotations Use annotations to register beans with Spring containers. Register in applicationContext. xml . For example, specify a package in

Struts2-generation history step by stepStruts2 step by step generation History 1 JSP: In earlier web applications, html static pages were used. jsp embedded java scripts in HTML files to achieve page dynamics. HTML tags are used to layout and

In spring, @ RequestBody is used, and the corresponding bean's attribute name writes are empty. Recently, the project used the new spring feature @ RequestBody, which is very useful. The json string sent by the client is directly converted and

How to add controls to the Silverlight layout panel   How to add controls to the Silverlight layout panel How to add text:   TextBlock txt = new TextBlock (); txt. text = tmc; txt. fontSize = 12; txt. foreground = t_brush; txt. flowDirection =

Struts2 ---- interceptorWhat is an interceptor: Interceptor, used in AOP (Aspect-OrientedProgramming) to intercept a method or field before it is accessed, and then add some operations before or after it. Interception is an implementation policy of