The result of mybatis query is actually List list = {null}
will enter the loop traversal code, in the loop inside T = null will be a null pointer exception
Solution:
1. Remove the empty object element from list: list.removeAll(Collections.singleton(null));
2. Add ifnull (.... ,0).to the select field in the SQL statement.
Read More:
- Not showing null elements JAVA [How to Solve]
- [Solved] Mybatis insert Error: Cause: java.sql.SQLException: SQL String cannot be empty
- [Solved] com.alibaba.fastjson.JSONException: syntax error, pos 1, json
- Mybatis sets the primary key Auto-Increment error: No setter found for the keyProperty
- JAVA: How to Solve Foreach Loop Remove/add Element Error
- [Solved] Mybatis integrates PageHelper and uses sqlserver paging error
- Ruoyi-cloud Integrated mybatis-plus Error: Unknown column ‘search_value‘ in ‘field list‘
- [Solved] Error getting generated key or setting result to parameter object. UnsupportedOperationException
- Mybatis single parameter pass in exception (How to Fix)
- [Solved] write javaBean error, fastjson version 1.2.76, class org.apache.flink.table.data.binary
- JAVA: How to Read JSON Format Data (Web Game Development)
- Request processing failed; nested exception is java.lang.NullPointerException or UnsatisfiedDependencyE
- I/O error while reading input message; nested exception is java.io.IOException: Stream closed
- How to Solve SQL comments error in the mybatis query
- Mybatis Error: All elements are null [How to Solve]
- [Solved] Method threw ‘java.lang.StackOverflowError‘ exception. Cannot evaluate
- List: How to de-duplication according to an attribute of an object
- JUnit tests mybatis-plus error: null pointer [How to Solve]
- Mapper.xml Error: Error setting non null for parameter #3 with JdbcType null.
- Mybatis Error: The error may exist in xxxxMapper.xml [How to Solve]