按行输出log日志文件里的日志,

@GET
@Path("viewlog")
@Produces("text/plain;charset=UTF-8")
public String viewLog(@QueryParam("s") Integer s,@QueryParam("k") String k) {
String logpath = ConfigHelp.getProperty("logpath");
StringBuffer sb = new StringBuffer();
try {
RandomAccessFile rf = null;
rf = new RandomAccessFile(logpath, "r");
long len = rf.length();
long start = rf.getFilePointer();
long nextend = start + len - 1;
String line;
rf.seek(nextend);
int c = -1;
int size = 0;
while (nextend > start && size < ((null == s) ? 30 : s)) {
c = rf.read();
if (c == '\n' || c == '\r') {
line = rf.readLine();
if (line != null) {
String str = new String(line.getBytes("ISO-8859-1"), "utf-8");
if(StringUtils.isEmpty(k) || (StringUtils.isNotEmpty(k) && str.contains(k))){
sb.append(str).append("\r\n").append("\r\n");
size++;
}
}
nextend--;
}
nextend--;
rf.seek(nextend);
if (nextend == 0) {// 当文件指针退至文件开始处，输出第一行
String str = new String(rf.readLine().getBytes("ISO-8859-1"), "utf-8");
if(StringUtils.isEmpty(k) || (StringUtils.isNotEmpty(k) && str.contains(k))){
sb.append(str);
size++;
}
}
}
rf.close();
} catch (Exception e) {
e.printStackTrace();
}
return sb.toString();
}