logwriter.java

这是一个自编的记事本程序

package cn.com.csuinfosoft.util;
import java.io.PrintWriter;
import java.io.StringWriter;
import java.util.Date;
public class LogWriter {
  public static final int NONE = 0;
  public static final int ERROR = 1;
  public static final int INFO = 2;
  public static final int DEBUG = 3;

  private static final String ERROR_TEXT = "error";
  private static final String INFO_TEXT = "info";
  private static final String DEBUG_TEXT = "debug";

  private PrintWriter pw;
  private String owner;
  private int logLevel;
  public LogWriter(String owner, int logLevel, PrintWriter pw){
     this.pw = pw;
     this.owner = owner;
     this.logLevel = logLevel;
  }

  public LogWriter(String owner, int logLevel){
     this(owner, logLevel, null);
  } 
  public int getLogLevel() {
     return logLevel;
  }

  public PrintWriter getPrintWriter() {
     return pw;
  }

  public void setLogLevel(int logLevel){
     this.logLevel = logLevel;
  }

  public void setPrintWriter(PrintWriter pw){
     this.pw = pw;
  }
  public void log(String msg, int severityLevel){
    if (pw != null){
      if (severityLevel <= logLevel){
        pw.println("[" + new Date() + "]  " +
        getSeverityString(severityLevel) + ": " + owner + ": " + msg);
      }
    }
  }

  public void log(Throwable t, String msg, int severityLevel)  {
    log(msg + " : " + toTrace(t), severityLevel);
  }

  private String getSeverityString(int severityLevel) {
     switch (severityLevel)
     {
        case ERROR:
           return ERROR_TEXT;
        case INFO:
           return INFO_TEXT;
        case DEBUG:
           return DEBUG_TEXT;
        default:
           return "Unknown";
     }
  }

  private String toTrace(Throwable e) {
     StringWriter sw = new StringWriter();
     PrintWriter pw = new PrintWriter(sw);
     e.printStackTrace(pw);
     pw.flush();
     return sw.toString();
  }  
}