[Error record] The problem that the exe4j packaging program cannot set the jar package dependency (package the source code and the dependent library into the same jar package)

1. Problem description

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Encountered in [Error Record] IntelliJ IDEA exported executable jar package execution error (java.lang.ClassNotFoundException | No dependent library was selected when packaging) blog

java.lang.ClassNotFoundException: com.microsoft.sqlserver.jdbc.SQLServerDriver
        at java.net.URLClassLoader.findClass(Unknown Source)
        at java.lang.ClassLoader.loadClass(Unknown Source)
        at sun.misc.Launcher$AppClassLoader.loadClass(Unknown Source)
        at java.lang.ClassLoader.loadClass(Unknown Source)
        at java.lang.Class.forName0(Native Method)
        at java.lang.Class.forName(Unknown Source)

Error message, here is the following strategy when packaging;

Since the second Jar package packaging method was selected when compiling the IntelliJ IDEA program, the main program and dependent libraries were packaged separately;

The final main program and dependent libraries are separated, when using the main program, additional dependent libraries must be configured;

Here is another problem involved, want to use exe4j to package the above jar package into a Windows program,

Package the Jar package with the Java virtual machine and bundle it into an executable exe program;

However, when exe4j is packaged, the dependent library of the jar package cannot be set, and only one jar package can be set;

After studying the documentation of exe4j, I got the following conclusions:

• The exe4j packaging program cannot set jar package dependencies, but can only set a jni-related native .a static library and .so dynamic library dependency directory;
• Exe4j also cannot set the java command execution parameters, if the parameters can be set, you can set the dependent library through the -classpath option;
• There is another way to pass parameters through the command line, but the packaged program is a path interface program;

This is rather embarrassing, what IntelliJ IDEA packages is a jar package + several jar dependent libraries, which cannot be set into exe4j;

When exe4j is executed, an error will be reported, dependencies cannot be found, and related classes cannot be found naturally;

java.lang.ClassNotFoundException: com.microsoft.sqlserver.jdbc.SQLServerDriver
        at java.net.URLClassLoader.findClass(Unknown Source)
        at java.lang.ClassLoader.loadClass(Unknown Source)
        at sun.misc.Launcher$AppClassLoader.loadClass(Unknown Source)
        at java.lang.ClassLoader.loadClass(Unknown Source)
        at java.lang.Class.forName0(Native Method)
        at java.lang.Class.forName(Unknown Source)

Two, the solution

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In IntelliJ IDEA, when exporting the jar package, select the first scheme setting, and then package all the java source code together;

The effect after packaging is as follows, all Java source codes are packaged in a jar package;

Note, to delete the signature file under the META-INF directory;

In [Error Record] IntelliJ IDEA packaged the Jar package containing the dependent library and reported an error (Invalid signature file digest for Manifest main attribute) blog, I encountered a problem with the signature file error;