0、Get installation package
1、Add the My.ini file to the bin directory. The contents are as follows
[mysql]
# Set MySQL client default character setdefault-character-set=utf8
[mysqld]
#Set 3306 portsPort= 3306
# Set up MySQL installation directoryBasedir=D:\mysql-5.7.23-win32
# Storage directory for setting up MySQL databaseDataDir=D:\mysql-5.7.23-win32\data
# Maximum number of connections allowedMax_connections=200
# The character set used by the server is defaults to the 8 bit coded Latin1 character set.Character-set-server=utf8
# Default storage engine that will be used when c...
1.Appearance pattern
To provide a consistent interface for a set of interfaces in a subsystem, this pattern defines a high-level interface that makes the subsystem easier to use.
2.Example
public class Cookie {
public void getBooks() {
System.out.println("cookie");
}
}
public class Tea {
public void apply() {
System.out.println("tea");
}
}
public class Facade {
public void doFacade(){
Tea tea = new Tea();
tea.apply();
Cookie cookie = new Cookie();
cookie.getBooks();
}
}
public class Client {
public static...
Question: at present, the station has received the uploaded data. After entering the controller layer, it is empty!!!
Solution: The name value of the tag uploaded, the value in requestParam (), the value in the corresponding parameter, the three names can not be the same. Submission mode post
For beginners, which way of submission is: do not use get as long as you remember data changes.
PooledDataSourceIt mainly involves two classes PooledConnection and PoolState.
PooledConnection：PooledDataSourceThe actual realConnection and proxyConnection link objects can be obtained from the database connection created inA dynamic proxy interface used
PoolState：Corresponding to the Pooled DataSource, the status of the connection pool corresponding to the data source is recorded, including idle, number of active links, and connection pool statistics.
PooledConnectionProperty description below;
Connection realConnection:The real connection for connecting to a database is the encapsulat...
meaning of the title：There are V classrooms. E has the right to have no edges (to ensure all classrooms are connected).
First there are n time periods, each time period, Niu Niu (volume.) Going to class $c_i$for class.
After class, he has to go to $c_{i+1}$for the next class.
At present, cattle can apply for m times, change the classroom, make the road less.
If I is applied to the time segment, the probability of $p_i$is changed to $d_i$with a probability of $c_i$(failure is equal to no change).
Of course, he can apply less or even apply.
...
Title Description
Statistics the number of digits in a sorted array.
thinking
The lowest method is still the count count.
Of course, when you look at an ordered array, you should think of the dichotomy, find the duplicate numbers on the left and right, and then subtract the two.
Answer
Method 1 count
class Solution:
def GetNumberOfK(self, data, k):
# write code here
if not data or len(data) ==0:
return 0
return data.count(k)
Method 2, do not use count counting method.
class Solution:
def GetNumberOfK(self, data, k):
# write code here
...
The Concurrent Markup Scan (CMS) collector is designed for applications that require shorter garbage collection pauses and can share processor resources with the garbage collector while the application is running.
For any application with low moratorium, this collector should be considered.
Using the command line option to enable the CMS collector-XX:+UseConcMarkSweepGC。
Like other available collectors, CMS collectors are generational; therefore, both small and major collections occur
CMSThe collector attempts to reduce pause time due to primary collection by tracking accessible objects ...
1.Enjoy element model
Pool technology is an important way to achieve, it can reduce the object created by the application, reduce the occupation of program memory, improve the performance of the program.
2.Example
public class Color {
private String color;
public String getColor() {
return color;
}
public void setColor(String color) {
this.color = color;
}
}
public class FlyWeight {
private Map<String, Color> colors = new HashMap<>();
public Color getColor(String str) {
if (colors.containsKey(str)) {
return colors.get(str);
} els...
