java.util.logging.FileHandler

java.util.logging.FileHandler

java自带的日志功能，FileHandler可以写日志到文件系统，并且自己维护日志的增删，比c++不知道强多少

FileHandler(filename,2,2); 测试时只写2k，并只保留2个文件：

 1 import java.io.IOException;
 2 import java.util.logging.FileHandler;
 3 import java.util.logging.Logger; // <= (1)
 4 
 5 public class Loggertest {
 6     
 7     private static Logger log = Logger.getLogger(Loggertest.class.getSimpleName());// <= (2)
 8     public void sub()
 9     {
10         String filename="D:\\test\\1.txt";
11         FileHandler fh;
12         try {
13             fh = new FileHandler(filename,2,2);
14             log.addHandler(fh);
15             
16             log.info("  1String userDir = System.getenv(\"USERPROFILE\");");// <= (3)
17             log.info("  2String userDir = System.getenv(\"USERPROFILE\");");// <= (3)
18             log.info("  3String userDir = System.getenv(\"USERPROFILE\");");// <= (3)
19             log.info("  4String userDir = System.getenv(\"USERPROFILE\");");// <= (3)
20             log.info("  5String userDir = System.getenv(\"USERPROFILE\");");// <= (3)
21             log.info("  6String userDir = System.getenv(\"USERPROFILE\");");// <= (3)
22             log.info("  7String userDir = System.getenv(\"USERPROFILE\");");// <= (3)
23             log.info("  8String userDir = System.getenv(\"USERPROFILE\");");// <= (3)
24             log.info("  9String userDir = System.getenv(\"USERPROFILE\");");// <= (3)
25             log.info("  10String userDir = System.getenv(\"USERPROFILE\");");// <= (3)
26             log.info("  11String userDir = System.getenv(\"USERPROFILE\");");// <= (3)
27             log.info("  12String userDir = System.getenv(\"USERPROFILE\");");// <= (3)
28             
29             log.info("  13String userDir = System.getenv(\"USERPROFILE\");");// <= (3)
30             log.info("  14String userDir = System.getenv(\"USERPROFILE\");");// <= (3)
31             log.info("  15String userDir = System.getenv(\"USERPROFILE\");");// <= (3)
32             log.info("  16String userDir = System.getenv(\"USERPROFILE\");");// <= (3)
33             log.info("  17String userDir = System.getenv(\"USERPROFILE\");");// <= (3)
34             log.info("  18String userDir = System.getenv(\"USERPROFILE\");");// <= (3)
35             log.info("  19String userDir = System.getenv(\"USERPROFILE\");");// <= (3)
36             log.info("  20String userDir = System.getenv(\"USERPROFILE\");");// <= (3)
37             log.info("  21String userDir = System.getenv(\"USERPROFILE\");");// <= (3)
38             log.info("  22String userDir = System.getenv(\"USERPROFILE\");");// <= (3)
39         } catch (SecurityException e) {
40             // TODO Auto-generated catch block
41             e.printStackTrace();
42         } catch (IOException e) {
43             // TODO Auto-generated catch block
44             e.printStackTrace();
45         } 
46     }
47 
48     public static void main(String[] args)
49     {
50         Loggertest logWorld = new Loggertest();
51         logWorld.sub();
52     }
53 }