_processClassPathList(list) {

        const ext = '.jar'
        const extLen = ext.length
        for(let i=0; i<list.length; i++) {
            const extIndex = list[i].indexOf(ext)
            if(extIndex > -1 && extIndex  !== list[i].length - extLen) {
                list[i] = list[i].substring(0, extIndex + extLen)
            }
        }

    }
Ensure that the classpath entries all point to jar files.

@param {Array.<String>} list Array of classpath entries.