在jar文件中使用java -cp时出错

Question

I am trying to run a jar file using java -cp but it keeps giving me error that could not find or load main class.

Here is my bat file

:: install.bat
:: run the installer jar as a windows bat file
::
@echo off

:: setup some properties
set CLASSES=.
set JAVA_OPTS=


:: build a basic classpath
set CP="%CLASSES%"

:: locate the java executable
set JAVA_EXE="%JAVA_HOME%\bin\java.exe"
IF EXIST "%JAVA_EXE%" GOTO start
set JAVA_EXE=java.exe

:start
:: show off java version info
echo -------------------------------------------------
"%JAVA_EXE%" -version
REM echo     JAVA_OPTS: %JAVA_OPTS%
REM echo     CLASSPATH: %CP%
echo -------------------------------------------------

:: start the program
%JAVA_EXE% %JAVA_OPTS% -cp %CP% -    Djava.util.logging.config.file="./enr_logging.properties" com.company.product.package.MainClass

Assuming that my fully qualified class name is com.company.product.package.MainClass and the jar is in the same folder as the .bat file

Answer 1

Running a jar with -cp requires the classpath to list the jar, for instance :

java -cp "Test.jar;lib/*" my.pretty.MainClass

NB : Test.jar can be replaced by * to match all jars, but *.jar won't work.

Alternatively, you can run the jar with -jar . This method requires the classpath to be defined in the jar's manifest and silently ignores other classpath declarations.