1.SpringMVC and front / back of json data exchange
https://blog.csdn.net/zmx729618/article/details/78779073
2. province, city, district three linkage (or import jquery plugins jquery plugins directly in the library)
https://www.cnblogs.com/zhujiabin/p/4995591.html
3.dom4 examples analytical
https://www.cnblogs.com/Toolo/p/JavaDom4j.html
4.Spring CI <context: annotation-config > explanation
https://www.cnblogs.com/_popc/p/3972212.html
differences and usage 5. @ Autowired @Resource notes and annotations
https://blog.csdn.net/changqi008/article/details/ 83,003,669
use @Resource annotation on the field, so you do not need to write a setter method, and this property is part of J2EE, which can reduce the coupling of the spring of
6.sql server 2008 installation prompts Restart computer failed
https://zhidao.baidu.com/question/1239251825799710419.html? qbl = relate_question_1 & word = % D4% F5% C3% B4% BD% E2% BE% F6% B0% B2% D7% B0SqlServer2008% D7% DC% CA CC C7% E1%%%% CA% BERestart 20computer% 20AS% 20failed
7.Invalid bound of Statement (not found) possible cause of the error
https://www.cnblogs.com/liaojie970/p/8034525.html
8.Java connection Server 2008 the SQL
https://blog.csdn.net/qq243920161/article/details/78971861
9. the front end of the data derived json js code
https://www.cnblogs.com/lxk233/p/10224164.html
10. the three background difference kinds of traversal methods
common for \ enhancements for \ Iterator
11. @ responseBody and @ResquestBody usage
NOTE: each method will be added responseBody ??
problems encountered in the development of 12.
1) project running on the local no question, deployed to the server appear three linkage data is not
the problem: js file Chinese garbled data can not show cause
problem analysis and solutions: All files are encoded format utf-8, deployed on the server,
The coding of this document should be changed to ASCII
2) Chinese sqlserver database insert garbled data, a variety of situations as follows:
Solution:
1. not set up a data table
Note Sort the table is built table Chinese_PRC_90_CI_AS
2. Data Sheet has been established when, without deleting data, will sort all fields strap Chinese changed Chinese_PRC_90_CI_AS, while the data type to nvachar
3) ajax realize the front page and file export capabilities of design ideas
1. export excel file
after passing through the json ajax request returns the result set of data assigned to a global variable, the definition of the header field into a string in Chinese, the data corresponding to the corresponding values json by looping through.
Click to download the results achieved by the creation of a a label var link = document.createElement ( "a" ), by link.download = "" create a file name, the file data is added to
2. Page
added plug-ins, the number of pages assigned to the global variable, the output of the control loop Article number
always reported version 4) server version jdk1.7, local jdk 1.8, all versions of the same control, call the SF print pictures jar packet error
solution: see log files It found that the error points to a class jar package, opening the compiled version is found jdk1.8. Since the jar file can not be recompiled, jdk 1.8 will change the server to solve the problem
based on: jdk version is backward compatible
5) database can not connect, the error message: Incompatible version
Error reason: for low version of the driver package
13. The @Autowired (required = false) MaterialMapper materialMapper;
14.JQuery selector click on the object to get the current id, name, value property by a click event
https://blog.csdn.net/ qq_34873338 / Article This article was / Details / 71,189,938
15. A disconnection error BeanFactory not initialized or already closed - call 'refresh' before accessing beans via the ApplicationContext
Profile in question, which is not simply a local reference
16. A single field is too long, select the appropriate length of the display, the remaining portion of hide may then add the corresponding fields in the suspension frame
when the given connection 17. The configuration database inconsistent versions
reason: the version of the driver package to a corresponding
18.ajax json data transfer format in the data to the background, if desired also need to accept the value returned in the background to the corresponding package json data format, if it is a boolean value,
Only you need to write the true or false logic code distal success callback function
19. The local environment is jdk1.8, the company server is jdk1.7. Sdk print SF official website says the service is jdk1.7 and above,
without having to change their re-jdk version, just only need to download jdk1.7, and himself the project compiled with jdk1.7.
When exclude the interference of other factors when deploying to the server is still reported the wrong version. After careful examination revealed SF jar package provides printing services are all jdk1.8, the
last jdk on the company server can only be replaced by 1.8. (jdk operating environment and compiler environment backward compatible, of course, different versions of the jdk tomcat need to correspond to the appropriate version)
20. On the front-end to achieve some style issues, in order to improve development efficiency, can go to the library jquery download the appropriate plug-ins (for example, plug-time, the suspension block, balloon, three areas linkage)
parameters 21. springmvc framework, we do not pass the parameters in the controller httpServlet layer of quotation springMvc automatic transmission will be encapsulated into the foreground objects
22. ssm frame, the core of the scanner is configured for each layer, such as @ controller, @ service, @ component , Once configured we can directly use the object corresponding to the
main architecture: mapper layer write sql statement and methods of the interface
service layer directly call mapper corresponding method, Controller layer calls the service layer
if the service is more complex, data processing logic to the query with a code layer as the dao proposed to increase the implementation class mapper layer, the service layer directly call
ps: injection of two ways spring (1. 2. Notes configuration file)
23. In the implementation file ajax derived, if the value field contains a comma, he will be taken into two, the need for processing the string
24. The format of the date of conversion
in the layer sql statement: convert (nvarchar, date, 23 ) converting YY-MM-DD to form
the background: SimpleDateFormat df = new SimpleDateFormat ( " yyyyMMdd"); // set the date format
orderid = "ZY -" + df.format (new date ()) + str;
front: fmt tag ( import tab library), JS, regular expressions, jsr 303, Hiberbate Validator (jsr 303 extension, into which 5 jar package)
25.sql optimization
1. indexed in the table, to use where.group by priority field .
2. query, be sure not to use select *, will return too many useless because the field will reduce the query efficiency. Should be used instead of specific fields *, only to return to the field.
3. Do not use in conditions where the left and right sides are% of fuzzy query like, to make use of fuzzy search field behind
4. Do not use in and not in, with continuous values BETWEEN
5. The try not to use or, may cause the whole table scan, with union
try not to carry out field operations expression in the where clause 6, it will also result in a full table scan.
Analyzing conditions in 7.where try not null value, the null will cause full table scan is determined (field applied to the default value, e.g. 0 or empty)
8. Do not use the condition where 1 = 1
9. Try not to carry out the expression on the left side where moderate number of conditions. Function operation, will lead to a full table scan
10. The program should try to avoid large transaction operations, improve system concurrency.
11. The index number of a table is best not more than six
26.spring Affairs (simply to avoid procedural failures lead to operation of the database is incomplete, use transaction can maintain data consistency)
https://www.cnblogs.com /yixianyixian/p/8372832.html
knowledge points:
1.Spring does not directly manage affairs, but offers a variety of transaction manager, who will entrust responsibility or Hibernate transaction management to JTA persistence mechanism such as provided by the relevant transaction platform framework to achieve
2.Spring transaction Manager Interface is the org.springframework.transaction.PlatformTransactionManager
3. transaction management across multiple sources (such as two or more different data sources), you will need to use JtaTransactionManager
4.Hibernate has been a de facto standard Java persistence, but now Java persistence API as a true standard Java persistence
5. use declarative transaction spring, spring using AOP to support declarative transaction, the transaction will be based on attributes, automatically decide whether to open a transaction, and decided to submit the transaction or roll back the transaction after the method call is performed before
6. Transaction should have four properties: atomicity, consistency, isolation, durability. These four properties are usually called ACID properties.
27.ssm framework for implementing transaction management in the form of annotations
https://blog.csdn.net/zhshulin/article/details/38108159
28. The transaction isolation level
Dirty read:
non-repeatable reads: focus is to modify the
phantom read: that add or delete
29.Spring transaction rollback mechanism to understand
spring aop exception trap principle: method intercepted require an explicit exception is thrown, and not any treatment, so aop proxy to capture the abnormal method, can be rolled back by default aop capture runtimeexception only exception
when the exception is caught when (catch), spring transaction can not be rolled back, if you want to let the spring to capture the transaction, you need to continue to throw an exception
understand: 1 instance method on a call for data entry operations, but in the back operation exception is thrown, and the transaction management sping and arranged to capture the exception, the previous data will rollback operation
abnormality 2. another way is determined by the program control, to avoid the occurrence of the run
3 .spring propagated in two common configuration transaction and the transaction isolation level
https://www.cnblogs.com/dj66194/p/7654555.html
30.spring to Form of the solution to achieve transaction management
https://www.cnblogs.com/younggun/p/3193800.html
31.maven use
https://www.cnblogs.com/gaojinshun/p/11252438.html
1. Integration SSM (SpringMVC)
https://www.cnblogs.com/panda001/p/11247569.html
2. polymerization Project - Project such high reusability
3.Spring core support check data the API: SmartValidator
HTTPS : //www.cnblogs.com/fangshixiang/p/11249498.html
33. The data validation
34.ssm integration quartz, pure notes development (pro-test simple and practical)
https://blog.csdn.net/weixin_43832604/article/ Details / 88,862,926
https://blog.csdn.net/f641385712/article/details/96638596
https://blog.csdn.net/f641385712/article/details/96764829
35.JS replace all commas
str = str.replace (/ , / g, ""); // cancel all comma encountered in a string