python exceptions, modules and packages

1. Abnormal Exception: When an error is detected, the Python interpreter cannot continue to execute. Instead, some error prompts appear. This is the so-called “exception”, which is what we often call BUG. 1.1 Catching Exceptions Basic syntax: try: error code may occur except: Code to be executed if an exception occurs Code example: # Try […]

Instances of all methods in the list type (except sort) and explanations (called through help (list))

1. Overview After using help (list) and running it, you can see the following methods: append, clear, copy, count, extend, index, insert, pop, remove, reverse, a total of ten methods. Next, I will give examples one by one. explain. 2. Examples and explanations 1.append: Append object to the end of the list. (Append object to […]

RuntimeError: Sizes of tensors must match except in dimension 1. Expected size 58 but got size 57 fo

An error occurred: When using yolo v5n for network training, the input size used is 900*900. When connecting the Feature Map of the 11th layer and the 6th layer at the 12th layer Concat, there is a problem of different dimensions. After running, the following error message appears: RuntimeError: Sizes of tensors must match except […]

redis org.springframework.data.redis.RedisSystemException: Error in execution

Background When running a certain system, the test class stores a certain value into redis and then takes it out. 1. Problems encountered Error reported: org.springframework.data.redis.RedisSystemException: Error in execution; nested exception is io.lettuce.core.RedisCommandExecutionException: MISCONF Redis is configured to save RDB snapshots, but it is currently not able to persist on disk. Commands that may modify […]

Springboot2.x integrated lettuce connection redis cluster reports timeout exception Command timed out after 6 second(s)

Original/Zhu Jiqian Background: Recently, I was doing a stress test on a newly developed Springboot system. I found that when I first started the stress test, I could access data from the redis cluster normally. However, after a few minutes of pause, and then when I continued to use jmeter to perform the stress test, […]

SpringBoot application starts org.apache.catalina.LifecycleException

Table of Contents SpringBoot application starts org.apache.catalina.LifecycleException Problem Description Cause Analysis Solution 1. Check the resources that the application depends on 2. Check application configuration 3. Check port occupancy 4. Check dependent component version compatibility 5. Check the log files Application scenario example: org.apache.catalina.LifecycleExceptionexception caused by database connection exception SpringBoot application starts org.apache.catalina.LifecycleException When developing […]

org.hibernate.QueryException: could not instantiate class [com.ak47.cms.cms.dto.TechArticleDto] from

Table of Contents org.hibernate.QueryException: could not instantiate class [com.ak47.cms.cms.dto.TechArticleDto] from tuple Abnormal background solution in conclusion org.hibernate.QueryException: could not instantiate class [com.ak47.cms.cms.dto.TechArticleDto] from tuple When performing Hibernate-based data query, you may encounter an exception similar to ??org.hibernate.QueryException: could not instantiate class??, especially when using DTO (Data Transfer Object) from When mapping data in query results. […]

Solve javax.persistence.RollbackException: Transaction marked as rollbackOnly Ask

Table of Contents Solve javax.persistence.RollbackException: Transaction marked as rollbackOnly Ask Abnormal 1. Apply logic 2. Persistence context issues 3. Restraint violations Approach 1. Check application logic 2. Review persistence context management 3. Check for constraint violations 4. Exception handling and logging 5. Reference documentation and community support in conclusion Resolving javax.persistence.RollbackException: Transaction marked as rollbackOnly […]

The saveBatch of mybatis-plus reports an error, but there is no problem with save? Null pointer Caused by: java.lang.NullPointerException

Null pointer problem in batch operations such as saveBatch in mybatis-plus describe: Error message Solutions solution doubt Reference blog Description: It’s almost time to get off work again, haha. I hope I can help you. I’ll explain it in a scribble. Null pointers will appear in batch operations, but there is no problem in a […]

Python Exception Handling: Exploration and Best Practices of Three Different Approaches

PythonException handling: exploration and best practices of three different methods Foreword This article aims to explore three different exception handling methods in Python. By having a deep understanding of various exception handling strategies, we can better deal with different programming scenarios and choose the method that best suits our needs. Exception handling plays a vital […]