0

我在他们各自的文件中有以下来自一本书的示例代码，每个文件都与其中定义的接口或类具有相同的名称：

Logger.java 

package logging;

public interface Logger
{
   boolean connect();
   boolean disconnect();
   boolean log(String msg);
}

LoggerFactory.java 

package logging;

public abstract class LoggerFactory
{
   public final static int CONSOLE = 0;
   public final static int FILE = 1;

   public static Logger newLogger(int dstType, String... dstName)
   {
      switch (dstType)
      {
         case CONSOLE: return new Console(dstName.length == 0 ? null : dstName[0]);
         case FILE   : return new File(dstName.length == 0 ? null : dstName[0]);
         default     : return null;
      }
   }
}

Console.java 

package logging;

class Console implements Logger
{
   private String dstName;

   Console(String dstName)
   {
      this.dstName = dstName;
   }

   @Override
   public boolean connect()
   {
      return true;
   }

   @Override
   public boolean disconnect()
   {
      return true;
   }

   @Override
   public boolean log(String msg)
   {
      System.out.println(msg);
      return true;
   }
}

File.java 

package logging;

class File implements Logger
{
   private String dstName;

   File(String dstName)
   {
      this.dstName = dstName;
   }

   @Override
   public boolean connect()
   {
      if (dstName == null)
         return false;
      System.out.println("opening file " + dstName);
      return true;
   }

   @Override
   public boolean disconnect()
   {
      if (dstName == null)
         return false;
      System.out.println("closing file " + dstName);
      return true;
   }

   @Override
   public boolean log(String msg)
   {
      if (dstName == null)
         return false;
      System.out.println("writing "+msg+" to file " + dstName);
      return true;
   }
}

TestLogger.java 

// package logging;

import logging.Logger;
import logging.LoggerFactory;

public class TestLogger
{
   public static void main(String[] args)
   {
      Logger logger = LoggerFactory.newLogger(LoggerFactory.CONSOLE);
      if (logger.connect())
      {
         logger.log("test message #1");
         logger.disconnect();
      }
      else
         System.out.println("cannot connect to console-based logger");
      logger = LoggerFactory.newLogger(LoggerFactory.FILE, "x.txt");
      if (logger.connect())
      {
         logger.log("test message #2");
         logger.disconnect();
      }
      else
         System.out.println("cannot connect to file-based logger");
      logger = LoggerFactory.newLogger(LoggerFactory.FILE);
      if (logger.connect())
      {
         logger.log("test message #3");
         logger.disconnect();
      }
      else
         System.out.println("cannot connect to file-based logger");
   }
}

所有这些文件都在一个名为logger. 这本书说执行javac TestLogger.java应该在目录中找到并编译所有必要的类文件logger，但我得到一个错误 

TestLogger.java:3: error: package logging does not exist
import logging.Logger;
              ^

其次是其他错误，主要与找不到logging包有关。为什么这个程序不编译？我尝试创建指向父文件夹的 CLASSPATH 系统变量，logging并尝试
javac -classpath "parent_folder_of_logging" TestLogger.java但没有任何效果。这里有什么问题，我该如何解决？

4

4 回答 4

3

转到日志记录的父文件夹并执行：

 javac logging/TestLogger.java

在同一个文件夹中执行

 java logging.TestLogger
于 2013-07-25T05:47:17.517 回答
1

将所有文件放入logger目录

从记录器目录外执行

javac logging/TestLogger.java
于 2013-07-25T05:50:41.950 回答
1

类 TestLogger 必须在其他包中！

于 2013-07-25T05:51:47.563 回答
0

基本上，您需要将所有文件放在具有名称日志记录的目录中，然后从目录外部运行应用程序并使用

javac -cp classpath classname

java -cp classpath packagename.classname
于 2013-07-25T05:48:26.223 回答