場景

1.throws是在方法上拋出異常，throw是在語句上拋出異常。

2.try-catch是在catch里處理try捕獲異常并處理。

3.一般try-catch是在上層Controller中使用，而在Service以及dao層的接口上用throws向上級拋出異常。

避免踩坑：

在Controller中添加了try-catch，沒有在sevice以及dao層添加throws，導致在dao層調用mapper文件中

某方法時在if標簽中有錯誤時：

<if test="wmsReceiveOrder != null and wmsReceiveOrder.purchaseCode!=null and wmsReceiveOrder.purchaseCode!=''" >and ro.purchase_code=#{wmsReceiveOrder.purchaseCode} </if>

不會輸出異常信息。

實現

1.在Controller層添加try-catch

?? try {IPage<WmsReceiveOrderVO> page = receiveOrderService.pageTray(pageEntity, vo);Log.getInst(this).debug("doPageForRoleTable test:" + vo.getColumns().get(0).getSearch());return dataTablesResultJsonVO;} catch (Exception ex) {Log.getInst().debug("獲取收貨單數據接口:",ex);Log.getInst(this).debug("doPageForRoleTable test:" + vo.getColumns().get(0).getSearch());return dataTablesResultJsonVO;}

2.調用service層時，需要在service的接口上添加throws

public interface IWmsReceiveOrderService extends IService<WmsReceiveOrder> {IPage<WmsReceiveOrderVO> pageTray(Page<WmsReceiveOrderVO> page, DataTablesJsonVO vo)? throws Exception; }

3.同樣在dao層接口上也要添加throws

public interface IWmsReceiveOrderService extends IService<WmsReceiveOrder> {IPage<WmsReceiveOrderVO> pageTray(Page<WmsReceiveOrderVO> page, DataTablesJsonVO vo)? throws Exception; }

4.其中Controller中分Log是在slf4j基礎上封裝的打印日志的工具類。

package com.ws.kernel.log;import org.slf4j.Logger; import org.slf4j.LoggerFactory;import java.util.HashMap; import java.util.Map;public class Log {private static String logPrefix = " log -> ";private static Log instance;private static Logger logger = null;private static Map<Class, Logger> loggerList = new HashMap<Class, Logger>();?//用于緩存logger對象/*** 定義私有構造方法實現單例*/private Log() {}/*** 功能說明：獲取服務實例的靜態方法* 修改說明：* @author badao* @date* @param obj 傳入調用此方法的對象* @return*/public synchronized static Log getInst(Object obj) {if (instance == null) {instance = new Log();}Log.logger = loggerList.get(obj.getClass());if (Log.logger == null) {Log.logger = LoggerFactory.getLogger(obj.getClass());//Log.logger = Logger.getLogger(obj.getClass());loggerList.put(obj.getClass(), Log.logger);}return instance;}/*** 功能說明：獲取服務實例的靜態方法* 修改說明：* @author baadao* @date* @param clazz 傳入調用此方法的類型* @return*/public synchronized static Log getInst(Class clazz) {if (instance == null) {instance = new Log();}Log.logger = loggerList.get(clazz);if (Log.logger == null) {Log.logger = LoggerFactory.getLogger(clazz);loggerList.put(clazz, Log.logger);}return instance;}/*** 功能說明：獲取服務實例的靜態方法* 修改說明：* @author badao* @date* @return*/public synchronized static Log getInst() {if (instance == null) {instance = new Log();}Log.logger = loggerList.get(Log.class);if (Log.logger == null) {Log.logger = LoggerFactory.getLogger(Log.class);loggerList.put(Log.class, Log.logger);}return instance;}public void trace(String message) {Log.logger.trace(logPrefix + message);}public void trace(String message, Throwable t) {Log.logger.trace(logPrefix + message, t);}public void debug(String message) {Log.logger.debug(logPrefix + message);}public void debug(String message, Throwable t) {Log.logger.debug(logPrefix + message, t);}public void info(String message) {Log.logger.info(logPrefix + message);}public void info(String message, Throwable t) {Log.logger.info(logPrefix + message, t);}public void warn(String message) {Log.logger.warn(logPrefix + message);}public void warn(String message, Throwable t) {Log.logger.warn(logPrefix + message, t);}public void error(String message,Object... arguments) {Log.logger.error(logPrefix + message,arguments);}public void error(String message, Throwable t, Object... arguments) {Log.logger.error(logPrefix + message,t,arguments);} }

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