Question

我无法让apache commons cli工作。

我有一个最简单的开始：这是唯一的课程。使用maven（命令行）添加资源。

import org.apache.commons.cli.*;

public class App {

    public static void main(String[] args) {

        // create Options object
        Options options = new Options();
        CommandLineParser parser = new DefaultParser();

        // add t option
        options.addOption("t", false, "display current time");

        try{
            CommandLine cmd = parser.parse( options, args);
        }catch(ParseExeption ex){

        }

        if(cmd.hasOption("t")) {
            // print the date and time
        }else {
            // print the date
        }
    }
}

无论我尝试过什么。我得到＆＃34;找不到符号＆＃34;。这是错误的最后一部分：

 [ERROR] COMPILATION ERROR : 
 [INFO] -------------------------------------------------------------
 [ERROR] /Users/peter/Code/java/using_archetypes/using_cli_1/src/main
  /java/com/mkyong/core/utils/App.java:[27,8] cannot find symbol
  symbol:   class ParseExeption
  location: class com.mkyong.core.utils.App
  [ERROR] /Users/peter/Code/java/using_archetypes/using_cli_1/src/main 
  /java/com/mkyong/core/utils/App.java:[31,4] cannot find symbol
  symbol:   variable cmd
  location: class com.mkyong.core.utils.App
  [INFO] 2 errors 
  [INFO] -------------------------------------------------------------
  [INFO]   

  -------------------------------------------------------------------
  [INFO] BUILD FAILURE
  [INFO]   
  -------------------------------------------------------------------
  [INFO] Total time: 0.842 s
  [INFO] Finished at: 2016-10-31T12:17:29+01:00
  [INFO] Final Memory: 15M/309M
  [INFO]      
   ---------------------------------------------------------------
  [ERROR] Failed to execute goal org.apache.maven.plugins:maven-  
  compiler-plugin:3.1:compile (default-compile) on project   
  dateUtils2:  Compilation failure: Compilation failure:
  [ERROR] /Users/peter/Code/java/using_archetypes/using_cli_1/src/main
  /java/com/mkyong/core/utils/App.java:[27,8] cannot find symbol
  [ERROR] symbol:   class ParseExeption
  [ERROR] location: class com.mkyong.core.utils.App
  [ERROR] /Users/peter/Code/java/using_archetypes/using_cli_1/src/main 
   /java/com/mkyong/core/utils/App.java:[31,4] cannot find symbol
  [ERROR] symbol:   variable cmd
  [ERROR] location: class com.mkyong.core.utils.App
  [ERROR] -> [Help 1]
  [ERROR] 
  [ERROR] To see the full stack trace of the errors, re-run Maven   
   with     the -e switch.
   [ERROR] Re-run Maven using the -X switch to enable full debug  
   logging.
   [ERROR] 
   [ERROR] For more information about the errors and possible   
    solutions, please read the following articles:
   [ERROR] [Help 1] http://cwiki.apache.org/confluence/display/MAVEN   
   /MojoFailureException

请帮我从commons-cli开始。这是使用maven编译器编译的。谢谢。

Answer 1

只需将ParseExeption替换为ParseException，然后将if / else块移动到与您定义变量cmd相同的代码块中，否则它将无法显示，因为例如下一个：

public static void main(String[] args) throws ParseException{
    // create Options object
    Options options = new Options();
    CommandLineParser parser = new DefaultParser();

    // add t option
    options.addOption("t", false, "display current time");

    CommandLine cmd = parser.parse( options, args);

    if(cmd.hasOption("t")) {
        // print the date and time
    }else {
        // print the date
    }

}

try-catch块后错误找不到符号

1 个答案: