自定义日志

import java.io.File;
import java.io.FileWriter;
import java.io.IOException;
import java.util.Date;

public class WriteLogUtil {

     private static String rootPath = "D:\\logs\\"; 
           
          /**
           * 将信息写到文件中
           * @param msg
           */ 
          @SuppressWarnings("deprecation")
          public static void writeMsgToFile(String msg) { 
              //删除之前的文件  
              delOldFile(); 
         
              FileWriter fileWriter = null; 
              try { 
                  fileWriter = new FileWriter(getFileName(),true); 
                  Date today = new Date(); 
                  String time = String.valueOf(today.getHours()) + ":" + String.valueOf(today.getMinutes()) + ":" + String.valueOf(today.getSeconds()); 
                  fileWriter.write("#" + time + "# [" + msg + "]" + "\r\n"); 
                  fileWriter.flush(); 
              } catch (IOException e) { 
                  System.out.println("### 写日志到文件异常 ### >>> " + e.getMessage()); 
                 e.printStackTrace(); 
              } finally { 
                  try { 
                      fileWriter.close(); 
                  } catch (IOException e) { 
                      System.out.println("### 关闭写日志的流异常 ### >>> " + e.getMessage()); 
                      e.printStackTrace(); 
                  } 
              } 
          } 
           
          /**
           * 删除之前的日志文件
           */ 
          @SuppressWarnings("deprecation")
          private static void delOldFile() { 
              Date today = new Date(); 
              int month = today.getMonth()+1; 
              month = month - 2; 
              if(month == -1) month = 11;  //一月份的日志产生則刪除11月份的
              if(month == 0)  month = 12;  //二月份的日志产生则删除12月份的，其它情况则删除前两个月的日志
              String delPath = rootPath + String.valueOf(month) + "\\"; 
              File folder = new File(delPath); 
              if(folder.exists()) { 
                  File[] files = folder.listFiles(); 
                  for(int i=0; i<files.length; i++) { 
                      files[i].delete(); 
                      System.out.println("删除成功！");
                  } 
              } 
          } 
           
          /**
           * 获取要保存的文件
           * @return fileName
           */ 
          @SuppressWarnings("deprecation")
          private static String getFileName() { 
                Date today = new Date(); 
              String fileName = String.valueOf((today.getYear()+1900)) + String.valueOf((today.getMonth()+1)) + String.valueOf(today.getDate()) + ".log"; 
               //创建目录  
              File folder = new File(rootPath + String.valueOf((today.getMonth()+1)) + "\\"); 
              if(!folder.exists()) { 
                  folder.mkdirs(); 
              } 
            //创建文件  
              File file = new File(rootPath + String.valueOf((today.getMonth()+1)) + "\\" +fileName); 
              if(!file.exists()) { 
                  try { 
                      file.createNewFile();
                      System.out.println("创建文件成功！"+file.getAbsolutePath());
                  } catch (IOException e) { 
                      System.out.println("###新建日志文件异常 ### >>> " + e.getMessage()); 
                      e.printStackTrace(); 
                  } 
              }
               
              fileName = rootPath + String.valueOf((today.getMonth()+1)) + "\\" + fileName; 
              return fileName; 
          } 
           
          /**
           * 测试使用的main方法
           */ 
          public static void main(String[] args) { 
             //getFileName();  
              String testString = "随便写吧"; 
              writeMsgToFile(testString); 
              //delOldFile();  
          } 

}