SpringBoot项目统一异常处理、统一日志处理、特定异常与自定义异常处理

统一异常、特定异常、自定义异常处理

想让项目中异常结果显示为统一的返回结果对象，并且统一处理系统的异常信息，需要统一异常处理。

创建统一异常处理类GlobalExceptionHandler

@ControllerAdvice
@Slf4j
public class GlobalExceptionHandler {

    //指定出现什么异常执行这个方法
    @ExceptionHandler(Exception.class)
    @ResponseBody //为了返回数据
    public R error(Exception e) {
        e.printStackTrace();
        return R.error().message("执行了全局异常处理..");
    }

    //特定异常
    @ExceptionHandler(ArithmeticException.class)
    @ResponseBody //为了返回数据
    public R error(ArithmeticException e) {
        e.printStackTrace();
        return R.error().message("执行了ArithmeticException异常处理..");
    }

    //自定义异常
    @ExceptionHandler(ZiDgYiException.class)
    @ResponseBody //为了返回数据
    public R error(ZiDgYiException e) {
        log.error(e.getMessage());
        e.printStackTrace();

        return R.error().code(e.getCode()).message(e.getMsg());
    }

}

创建自定义类ZiDgYiException

@Data
@AllArgsConstructor  //生成有参数构造方法
@NoArgsConstructor   //生成无参数构造
public class ZiDgYiException extends RuntimeException {
    private Integer code;//状态码
    private String msg;//异常信息
}

业务中需要抛出自定义异常的使用

        try {
            int i = 10/0;
        }catch(Exception e) {
            //执行自定义异常
            throw new ZiDgYiException(20001,"执行了自定义异常处理....");// 状态码与异常信息
        }

统一日志处理

1、配置日志级别

日志记录器（Logger）的行为是分等级的。
分为：OFF、FATAL、ERROR、WARN、INFO、DEBUG、ALL

默认情况下，spring boot从控制台打印出来的日志级别只有INFO及以上级别，可以配置日志级别

在配置文件中配置：

# 设置日志级别
logging.level.root=INFO

2、Logback日志

spring boot内部使用Logback作为日志实现的框架。
Logback和log4j非常相似，如果你对log4j很熟悉，那对logback很快就会得心应手。
logback相对于log4j的一些优点：https://blog.csdn.net/caisini_vc/article/details/48551287

由于冲突，删除application.properties中的日志配置
resources 中创建 logback-spring.xml

<configuration  scan="true" scanPeriod="10 seconds">
    
    
    
    

    <contextName>logbackcontextName>
    
    <property name="log.path" value="D:/yhd_info/edu" />

    
    
    
    
    
    
    
    <property name="CONSOLE_LOG_PATTERN"
              value="%yellow(%date{yyyy-MM-dd HH:mm:ss}) |%highlight(%-5level) |%blue(%thread) |%blue(%file:%line) |%green(%logger) |%cyan(%msg%n)"/>


    
    <appender name="CONSOLE" class="ch.qos.logback.core.ConsoleAppender">
        
        
        <filter class="ch.qos.logback.classic.filter.ThresholdFilter">
            <level>INFOlevel>
        filter>
        <encoder>
            <Pattern>${CONSOLE_LOG_PATTERN}Pattern>
            
            <charset>UTF-8charset>
        encoder>
    appender>


    

    
    <appender name="INFO_FILE" class="ch.qos.logback.core.rolling.RollingFileAppender">
        
        <file>${log.path}/log_info.logfile>
        
        <encoder>
            <pattern>%d{yyyy-MM-dd HH:mm:ss.SSS} [%thread] %-5level %logger{50} - %msg%npattern>
            <charset>UTF-8charset>
        encoder>
        
        <rollingPolicy class="ch.qos.logback.core.rolling.TimeBasedRollingPolicy">
            
            <fileNamePattern>${log.path}/info/log-info-%d{yyyy-MM-dd}.%i.logfileNamePattern>
            <timeBasedFileNamingAndTriggeringPolicy class="ch.qos.logback.core.rolling.SizeAndTimeBasedFNATP">
                <maxFileSize>100MBmaxFileSize>
            timeBasedFileNamingAndTriggeringPolicy>
            
            <maxHistory>15maxHistory>
        rollingPolicy>
        
        <filter class="ch.qos.logback.classic.filter.LevelFilter">
            <level>INFOlevel>
            <onMatch>ACCEPTonMatch>
            <onMismatch>DENYonMismatch>
        filter>
    appender>

    
    <appender name="WARN_FILE" class="ch.qos.logback.core.rolling.RollingFileAppender">
        
        <file>${log.path}/log_warn.logfile>
        
        <encoder>
            <pattern>%d{yyyy-MM-dd HH:mm:ss.SSS} [%thread] %-5level %logger{50} - %msg%npattern>
            <charset>UTF-8charset> 
        encoder>
        
        <rollingPolicy class="ch.qos.logback.core.rolling.TimeBasedRollingPolicy">
            <fileNamePattern>${log.path}/warn/log-warn-%d{yyyy-MM-dd}.%i.logfileNamePattern>
            <timeBasedFileNamingAndTriggeringPolicy class="ch.qos.logback.core.rolling.SizeAndTimeBasedFNATP">
                <maxFileSize>100MBmaxFileSize>
            timeBasedFileNamingAndTriggeringPolicy>
            
            <maxHistory>15maxHistory>
        rollingPolicy>
        
        <filter class="ch.qos.logback.classic.filter.LevelFilter">
            <level>warnlevel>
            <onMatch>ACCEPTonMatch>
            <onMismatch>DENYonMismatch>
        filter>
    appender>


    
    <appender name="ERROR_FILE" class="ch.qos.logback.core.rolling.RollingFileAppender">
        
        <file>${log.path}/log_error.logfile>
        
        <encoder>
            <pattern>%d{yyyy-MM-dd HH:mm:ss.SSS} [%thread] %-5level %logger{50} - %msg%npattern>
            <charset>UTF-8charset> 
        encoder>
        
        <rollingPolicy class="ch.qos.logback.core.rolling.TimeBasedRollingPolicy">
            <fileNamePattern>${log.path}/error/log-error-%d{yyyy-MM-dd}.%i.logfileNamePattern>
            <timeBasedFileNamingAndTriggeringPolicy class="ch.qos.logback.core.rolling.SizeAndTimeBasedFNATP">
                <maxFileSize>100MBmaxFileSize>
            timeBasedFileNamingAndTriggeringPolicy>
            
            <maxHistory>15maxHistory>
        rollingPolicy>
        
        <filter class="ch.qos.logback.classic.filter.LevelFilter">
            <level>ERRORlevel>
            <onMatch>ACCEPTonMatch>
            <onMismatch>DENYonMismatch>
        filter>
    appender>

    
    
    
    <springProfile name="dev">
        
        <logger name="com.yhd" level="INFO" />

        
        <root level="INFO">
            <appender-ref ref="CONSOLE" />
            <appender-ref ref="INFO_FILE" />
            <appender-ref ref="WARN_FILE" />
            <appender-ref ref="ERROR_FILE" />
        root>
    springProfile>


    
    <springProfile name="pro">

        <root level="INFO">
            <appender-ref ref="CONSOLE" />
            <appender-ref ref="DEBUG_FILE" />
            <appender-ref ref="INFO_FILE" />
            <appender-ref ref="ERROR_FILE" />
            <appender-ref ref="WARN_FILE" />
        root>
    springProfile>

configuration>

3、将错误日志输出到文件

GlobalExceptionHandler类上添加注解

 @Slf4j

异常输出语句，不同的值输出到相应的日志文件

 log.error(e.getMessage());
 log.info(e.getMessage());
 log.warn(e.getMessage());
 

4、将日志堆栈信息输出到文件

创建ExceptionUtil工具类

public class ExceptionUtil {
    public static String getMessage(Exception e) {
        StringWriter sw = null;
        PrintWriter pw = null;
        try {
            sw = new StringWriter();
            pw = new PrintWriter(sw);
            // 将出错的栈信息输出到printWriter中
            e.printStackTrace(pw);
            pw.flush();
            sw.flush();
        } finally {
            if (sw != null) {
                try {
                    sw.close();
                } catch (IOException e1) {
                    e1.printStackTrace();
                }
            }
            if (pw != null) {
                pw.close();
            }
        }
        return sw.toString();
    }
}

调用方法：

log.error(ExceptionUtil.getMessage(e));

ZiDgYiException中创建toString方法：

@Override
public String toString() {
    return "ZiDgYiException{" +
        "message=" + this.getMessage() +
        ", code=" + code +
        '}';
}