Solve the main class cannot be found or cannot be loaded error in Java

Scenario:

When using the java command to run the .class file, "Error: The main class cannot be found or cannot be loaded":

Reason:

1. By default, the java command searches for the address of the class file in the directory specified in the CLASSPATH environment variable. of.

2. Ignore the impact of package.

Solution:

Use the java package name and class name to execute, as follows: use java com.lznb.cloud.TCPEchoClient under src

Note:

Use the java command in the main directory to execute: java com.lznb.cloud.TCPEchoClient, the path is repeated , so here we need to execute it under src.

Summary:

1. The java execution class file is found according to the place specified by CLASSPATH, not the current directory that we understand. If you want it to query the current directory, you need to add ".;" to CLASSPATH to represent the current directory.

2. Java execution class files are strongly dependent on the package path. When it is executed, it will be strictly based on the current user path and convert the package path specified by the package into a file path to search for class files.

Recommended tutorial: java tutorial

The above is the detailed content of Solve the main class cannot be found or cannot be loaded error in Java. For more information, please follow other related articles on the PHP Chinese website!