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?????????????????????????????????????????????????bug?Java????????????????????????????????Eclipse?MyEclipse?????????????????????????????????????????????????????????

???????

????????????????log4j?Logging?commons-logging?slf4j?????????????????????

log4j??

log4j???????????????????????????????????log4j????????

log4j.rootLogger= ERROR, stdout
log4j.appender.stdout= org.apache.log4j.ConsoleAppender
log4j.appender.stdout.layout= org.apache.log4j.PatternLayout
log4j.appender.stdout.layout.ConversionPattern= %5p [%t] %m%n

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??????log4j?????????????????????ERROR?????????????????????????????

package com.log;
import org.apache.log4j.Logger;
public class Log4jTest {
    private static final Logger logger = Logger.getLogger(Log4jTest.class);
    
    public void test() {
        logger.debug("debug print");
        logger.info("info print");
        logger.warn("warn print");
        logger.error("error print");
    }
    
    public static void main(String[] args) {
        new Log4jTest().test();
    }
}

???????

???????????????DailyRollingFileAppender??????

log4j.rootLogger= ERROR, stdout, myLog
log4j.appender.stdout= org.apache.log4j.ConsoleAppender
log4j.appender.myLog= org.apache.log4j.DailyRollingFileAppender
log4j.appender.myLog.File= E:\testlog\log4j\server.log
log4j.appender.myLog.Append= true
log4j.appender.myLog.Threshold= DEBUG
log4j.appender.myLog.DatePattern= '.'yyyy-MM-dd
log4j.appender.myLog.layout= org.apache.log4j.PatternLayout
log4j.appender.myLog.layout.ConversionPattern= %-d{yyyy-MM-dd HH:mm:ss} [%t:%r] - [%p] [%c{1}:%L] [%M] %m%n
log4j.additivity.myLog= false

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?????????????????????????????????????????????

package com.log;
import java.io.BufferedWriter;
import java.io.FileOutputStream;
import java.io.IOException;
import java.io.OutputStreamWriter;
import java.text.SimpleDateFormat;
import java.util.Date;
public class FileLog {
    public static void writeLog(String file, String content) {
        BufferedWriter out = null;
        try {
            out = new BufferedWriter(new OutputStreamWriter(
                new FileOutputStream(file, true)));
            out.write(content);
            out.newLine();
        } catch (Exception e) {
            e.printStackTrace();
        } finally {
            try {
                out.close();
            } catch (IOException e) {
                e.printStackTrace();
            }
        }
    }
    public static void main(String[] args) {
        SimpleDateFormat df = new SimpleDateFormat("yyyy-MM-dd");
        SimpleDateFormat dfTime = new SimpleDateFormat("yyyy-MM-dd HH:mm:ss");
        Date date = new Date();
        String curTime = dfTime.format(date);
        String curDay = df.format(date);
        String text = "????" + org.apache.commons.lang.RandomStringUtils.randomNumeric(4);
        String logStr = "[" + curTime + "]" + text;
        String fileName = "E:/testlog/" + curDay + ".txt";
        System.out.println("start");
        writeLog(fileName, logStr);
        System.out.println("end");
    }
}

??????

?????????????????????????????????????????????????????????????????????????

package com.log;
import java.sql.Connection;
import java.sql.DriverManager;
import java.sql.PreparedStatement;
import java.sql.SQLException;
import java.util.Date;
public class DBLog {
    private static final String INSERT_LOG = "INSERT INTO tbl_log (content, create_time) VALUES (?, ?)";
    
    public static void writeLog(String content) {
        try {
            Connection conn = DriverManager.getConnection("jdbc:mysql://localhost:3306/logdb", "root", "password");
            PreparedStatement pstmt = conn.prepareStatement(INSERT_LOG);
            pstmt.setString(1, content);
            pstmt.setTimestamp(2, new Date());
            pstmt.executeUpdate();
            conn.commit();
        } catch (SQLException e) {
            e.printStackTrace();
        }
    }
    public static void main(String[] args) {
        DBLog.writeLog("????");
    }
}

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