java - 错误：找不到或加载主类[重复](Error: Could not find or load main class [duplicate])

Question

This question already has answers here) : 这个问题已经在这里有了答案) ：)

What does “Could not find or load main class” mean? “找不到或加载主类”是什么意思？) (45 answers) （45个答案）)

Closed 3 years ago . 3年前关闭。)

I am having trouble compiling and running my Java code, intended to allow me to interface Java with a shared object for Vensim, a simulation modeling package.

(我在编译和运行Java代码时遇到了麻烦，该代码旨在允许我将Java与模拟建模包Vensim的共享对象接口。)

The following code compiles without error:

(以下代码编译没有错误：)

javac -d . -cp ./apache-log4j-1.2.16/log4j-1.2.16.jar:./vensim.jar SpatialModel.java     VensimHelper.java VensimException.java VensimContextRepository.java

However, when I try to run the following:

(但是，当我尝试运行以下命令时：)

java -cp ./apache-log4j-1.2.16/log4j-1.2.16.jar:./vensim.jar SpatialModel vars

I get the following error: "Error: Could not find or load main class SpatialModel ".

(我收到以下错误：“错误：找不到或加载主类SpatialModel”。)

My SpatialModel.java code does contain a 'main' method (below), so I'm not sure what the problem is - can anyone please help me out?

(我的SpatialModel.java代码确实包含一个“主要”方法（如下），所以我不确定是什么问题-有人可以帮我吗？)

Thanks.

(谢谢。)

import java.io.File;
import java.text.NumberFormat;
import java.util.ArrayList;
import java.util.Arrays;
import java.util.List;

import org.apache.log4j.Logger;

public class SpatialModel {

    private VensimHelper vh;

    public static final String DLL_LIBNAME_PARAM = "vensim_lib_nam";

    public static final String MODEL_PATH_PARAM = "vensim_model_path";

    private final static int VENSIM_CONTEXT_CREATION_MAX_FAILURE_COUNT = 10;

    public SpatialModel() throws SpatialException {

        String libName = System.getProperty(DLL_LIBNAME_PARAM);
        String modelPath = System.getProperty(MODEL_PATH_PARAM);        

        if(libName == null || libName.trim().equals("")) {
            log.error("Vensim library name has to be set with -D" + DLL_LIBNAME_PARAM);
            throw new SpatialException("Vensim library name has to be set with -D" + DLL_LIBNAME_PARAM);
        }

        if(modelPath == null || modelPath.trim().equals("")) {
            log.error("Model path has to set with -D" + MODEL_PATH_PARAM);
            throw new SpatialException("Model path ahs to be set with -D" + MODEL_PATH_PARAM);
        }

        for (int i = 0; i < VENSIM_CONTEXT_CREATION_MAX_FAILURE_COUNT && vh == null; i++) {
            try {
                log.info("creating new vensim helper
dll lib: " + libName + "
model path: " + modelPath);
                vh = new VensimHelper(libName, modelPath);
            } catch (Throwable e) {
                log.error("An exception was thrown when initializing Vensim, try: " + i, e);
            }
        }
        if (vh == null) {
            throw new SpatialException("Can't initialize Vensim");
        }

    }

    public static void main(String[] args) throws VensimException {

        long before = System.currentTimeMillis();   
        String libName = System.getProperty(DLL_LIBNAME_PARAM);
        String modelPath = System.getProperty(MODEL_PATH_PARAM);

        if (libName == null) {
            libName = "libvensim";
        }
        if(modelPath == null) {
            modelPath = "~/BassModel.vmf";
        }

        System.setProperty(DLL_LIBNAME_PARAM, libName);
        System.setProperty(MODEL_PATH_PARAM, modelPath);

        if (args.length > 0 && args[0].equals("info")) {
            System.out.println(new VensimHelper(libName, modelPath).getVensimInfo());
        } else if (args.length > 0 && args[0].equals("vars")) {
            VensimHelper helper = new VensimHelper(libName, modelPath);
            String[] vars = helper.getVariables();
            for (String var : vars) {
                System.out.println(helper.getVariableInfo(var));
            }
        } else {

            File f = new File(".");
            System.out.println(f.getAbsolutePath());

            SpatialModel sm = new SpatialModel();
        }

        System.out.println("Execution time: " + (System.currentTimeMillis() - before));
    }

}

  ask by Dave translate from so

Answer 1

You must ensure that you add the location of your .class file to your classpath.

(您必须确保将.class文件的位置添加到类路径中。)

So, if its in the current folder, add .

(因此，如果它在当前文件夹中，请添加.)

to your classpath.

(到你的classpath。)

Note that the Windows classpath separator is a semi-colon, ie a ;

(请注意，Windows类路径分隔符是分号，即;)

.

(。)