JAVA工具类

SpringUtils

import org.springframework.beans.BeansException;
import org.springframework.beans.factory.config.BeanFactoryPostProcessor;
import org.springframework.beans.factory.config.ConfigurableListableBeanFactory;
import org.springframework.stereotype.Component;

/**
 * spring工具类 方便在非spring管理环境中获取bean
 */
@Component
public class SpringUtils implements BeanFactoryPostProcessor {

    private static ConfigurableListableBeanFactory beanFactory;

    @Override
    public void postProcessBeanFactory(ConfigurableListableBeanFactory configurableListableBeanFactory) throws BeansException {
        SpringUtils.beanFactory = configurableListableBeanFactory;
    }


    /**
     * 获取对象
     *
     * @param name
     * @return Object 一个以所给名字注册的bean的实例
     * @throws org.springframework.beans.BeansException
     */
    @SuppressWarnings("unchecked")
    public static <T> T getBean(String name) throws BeansException {
        return (T) beanFactory.getBean(name);
    }

    /**
     * 获取类型为requiredType的对象
     *
     * @param clz
     * @return
     * @throws org.springframework.beans.BeansException
     */
    public static <T> T getBean(Class<T> clz) throws BeansException {
        return (T) beanFactory.getBean(clz);
    }
}

MessageUtils

import com.hemou.ruoyi.common.utils.spring.SpringUtils;
import org.springframework.context.MessageSource;
import org.springframework.context.i18n.LocaleContextHolder;

/**
 * @Author HeMOu
 */
public class MessageUtils {

    /**
     * 根据消息键和参数 获取消息 委托给spring messageSource
     *
     * @param key 消息键
     * @param args 参数
     * @return 获取国际化翻译值
     */
    public static String message(String key, Object... args) {
        MessageSource messageSource = SpringUtils.getBean(MessageSource.class);
        return messageSource.getMessage(key, args, LocaleContextHolder.getLocale());
    }
}

AddressUtils

获取Ip的真实地址

import cn.hutool.http.HttpUtil;
import com.alibaba.fastjson.JSONObject;
import org.apache.commons.lang3.StringUtils;
import org.slf4j.Logger;
import org.slf4j.LoggerFactory;

import java.util.HashMap;

/**
 * 获取地址工具类
 *
 * @Author HeMOu
 */
public class AddressUtils {

    private static Logger log = LoggerFactory.getLogger(AddressUtils.class);

    public static final String IP_URL = "http://ip.taobao.com/service/getIpInfo.php";

    public static String getRealAddressByIP(String ip) {
        String address = "XX XX";
        // 内网不查询
        if (IpUtils.internalIp(ip)) {
            return "内网IP";
        }
        HashMap<String, Object> map = new HashMap<>();
        map.put("ip", ip);
        String rspStr = HttpUtil.post(IP_URL, map);
        if (StringUtils.isEmpty(rspStr)) {
            log.error("获取地理位置异常 {}", ip);
            return address;
        }
        try{
            JSONObject obj = JSONObject.parseObject(rspStr);
            JSONObject data = obj.getObject("data", JSONObject.class);
            String region = data.getString("region");
            String city = data.getString("city");
            address = region + " " + city;
            return address;
        }catch (Exception e){
            log.error("获取地理位置异常 {}", ip);
            return address;
        }
    }
}

ServletUtils

获取request和session对象

import cn.hutool.core.convert.Convert;
import org.springframework.web.context.request.RequestAttributes;
import org.springframework.web.context.request.RequestContextHolder;
import org.springframework.web.context.request.ServletRequestAttributes;

import javax.servlet.http.HttpServletRequest;
import javax.servlet.http.HttpServletResponse;
import javax.servlet.http.HttpSession;

/**
 * 客户端工具类
 */
public class ServletUtils {

    /**
     * 获取请求属性
     *
     * @return 请求属性
     */
    public static ServletRequestAttributes getRequestAttributes() {
        RequestAttributes attributes = RequestContextHolder.getRequestAttributes();
        return (ServletRequestAttributes) attributes;
    }

    /**
     * 获取session
     */
    public static HttpSession getSession() {
        return getRequest().getSession();
    }

    /**
     * 获取request
     *
     * @return request
     */
    public static HttpServletRequest getRequest() {
        return getRequestAttributes().getRequest();
    }

    /**
     * 获取response
     *
     * @return response
     */
    public static HttpServletResponse getResponse() {
        return getRequestAttributes().getResponse();
    }

    /**
     * 获取String参数
     */
    public static String getParameter(String name) {
        return getRequest().getParameter(name);
    }

    /**
     * 获取String参数
     */
    public static String getParameter(String name, String defaultValue) {
        return Convert.toStr(getRequest().getParameter(name), defaultValue);
    }


    /**
     * 获取Integer参数
     */
    public static Integer getParameterToInt(String name) {
        return Convert.toInt(getRequest().getParameter(name));
    }

    /**
     * 获取Integer参数
     */
    public static Integer getParameterToInt(String name, Integer defaultValue) {
        return Convert.toInt(getRequest().getParameter(name), defaultValue);
    }
}

需要注意的是，在SSM项目中如果直接使用该工具类，则会抛出一个空指针异常，原因是还需要在web.xml中配置一个监听器，代码如下：

<listener>
    <listener-class>
        org.springframework.web.context.request.RequestContextListener
    </listener-class>
</listener>

IpUtils

从request中获取ip地址。判断ip是否为内网地址

import javax.servlet.http.HttpServletRequest;
import java.net.InetAddress;
import java.net.UnknownHostException;

/**
 * 获取Ip工具类
 */
public class IpUtils {

    /**
     * 获取Ip地址
     *
     * @param request
     * @return
     */
    public static String getIpAddr(HttpServletRequest request) {
        if (request == null) {
            return "unknown";
        }
        String ip = request.getHeader("x-forwarded-for");
        if (ip == null || ip.length() == 0 || "unknown".equalsIgnoreCase(ip)) {
            ip = request.getHeader("Proxy-Client-IP");
        }
        if (ip == null || ip.length() == 0 || "unknown".equalsIgnoreCase(ip)) {
            ip = request.getHeader("X-Forwarded-For");
        }
        if (ip == null || ip.length() == 0 || "unknown".equalsIgnoreCase(ip)) {
            ip = request.getHeader("WL-Proxy-Client-IP");
        }
        if (ip == null || ip.length() == 0 || "unknown".equalsIgnoreCase(ip)) {
            ip = request.getHeader("X-Real-IP");
        }
        if (ip == null || ip.length() == 0 || "unknown".equalsIgnoreCase(ip)) {
            ip = request.getRemoteAddr();
        }
        return "0:0:0:0:0:0:0:1".equals(ip) ? "127.0.0.1" : ip;
    }


    public static boolean internalIp(String ip) {
        byte[] addr = textToNumericFormatV4(ip);
        return internalIp(addr) || "127.0.0.1".equals(ip);
    }

    private static boolean internalIp(byte[] addr) {
        if (addr == null || addr.length < 2) {
            return true;
        }
        final byte b0 = addr[0];
        final byte b1 = addr[1];
        // 10.x.x.x/8
        final byte SECTION_1 = 0x0A;
        // 172.16.x.x/12
        final byte SECTION_2 = (byte) 0xAC;
        final byte SECTION_3 = (byte) 0x10;
        final byte SECTION_4 = (byte) 0x1F;
        // 192.168.x.x/16
        final byte SECTION_5 = (byte) 0xC0;
        final byte SECTION_6 = (byte) 0xA8;
        switch (b0) {
            case SECTION_1:
                return true;
            case SECTION_2:
                if (b1 >= SECTION_3 && b1 <= SECTION_4) {
                    return true;
                }
            case SECTION_5:
                switch (b1) {
                    case SECTION_6:
                        return true;
                }
            default:
                return false;
        }
    }

    /**
     * 将IPv4地址转换成字节
     *
     * @param text IPv4地址
     * @return byte 字节
     */
    public static byte[] textToNumericFormatV4(String text) {
        if (text.length() == 0) {
            return null;
        }

        byte[] bytes = new byte[4];
        String[] elements = text.split("\\.", -1);
        try {
            long l;
            int i;
            switch (elements.length) {
                case 1:
                    l = Long.parseLong(elements[0]);
                    if ((l < 0L) || (l > 4294967295L))
                        return null;
                    bytes[0] = (byte) (int) (l >> 24 & 0xFF);
                    bytes[1] = (byte) (int) ((l & 0xFFFFFF) >> 16 & 0xFF);
                    bytes[2] = (byte) (int) ((l & 0xFFFF) >> 8 & 0xFF);
                    bytes[3] = (byte) (int) (l & 0xFF);
                    break;
                case 2:
                    l = Integer.parseInt(elements[0]);
                    if ((l < 0L) || (l > 255L))
                        return null;
                    bytes[0] = (byte) (int) (l & 0xFF);
                    l = Integer.parseInt(elements[1]);
                    if ((l < 0L) || (l > 16777215L))
                        return null;
                    bytes[1] = (byte) (int) (l >> 16 & 0xFF);
                    bytes[2] = (byte) (int) ((l & 0xFFFF) >> 8 & 0xFF);
                    bytes[3] = (byte) (int) (l & 0xFF);
                    break;
                case 3:
                    for (i = 0; i < 2; ++i) {
                        l = Integer.parseInt(elements[i]);
                        if ((l < 0L) || (l > 255L))
                            return null;
                        bytes[i] = (byte) (int) (l & 0xFF);
                    }
                    l = Integer.parseInt(elements[2]);
                    if ((l < 0L) || (l > 65535L))
                        return null;
                    bytes[2] = (byte) (int) (l >> 8 & 0xFF);
                    bytes[3] = (byte) (int) (l & 0xFF);
                    break;
                case 4:
                    for (i = 0; i < 4; ++i) {
                        l = Integer.parseInt(elements[i]);
                        if ((l < 0L) || (l > 255L))
                            return null;
                        bytes[i] = (byte) (int) (l & 0xFF);
                    }
                    break;
                default:
                    return null;
            }
        } catch (NumberFormatException e) {
            return null;
        }
        return bytes;
    }

    public static String getHostIp() {
        try {
            return InetAddress.getLocalHost().getHostAddress();
        } catch (UnknownHostException ignore) {}
        return "127.0.0.1";
    }

    public static String getHostName() {
        try {
            return InetAddress.getLocalHost().getHostName();
        } catch (UnknownHostException ignore) {}
        return "未知";
    }
}

Servlet项目工具

CommUtil

需要 beanutils

public class CommonUtil {

    /**
     * 返回一个不重复的字符串
     * @return
     */
    public static String uuid() {
        return UUID.randomUUID().toString().replace("-", "").toUpperCase();
    }

    /**
     * 把 map 转换成对象
     * @param map
     * @param clazz
     * @return 把Map转换成指定类型
     */
    @SuppressWarnings("rawtypes")
    public static <T> T toBean(Map map, Class<T> clazz) {
        try {
            /*
             * 1. 通过参数clazz创建实例
             * 2. 使用BeanUtils.populate把map的数据封闭到bean中
             */
            T bean = clazz.newInstance();
            ConvertUtils.register(new DateConverter(), java.util.Date.class);
            BeanUtils.populate(bean, map);
            return bean;
        } catch(Exception e) {
            throw new RuntimeException(e);
        }
    }
    
    public static class DateConverter implements Converter {

        @SuppressWarnings("unchecked")
        @Override
        public Object convert(Class type, Object value) {
            if(value == null) return null;//如果要转换成值为null，那么直接返回null
            if(!(value instanceof String)) {//如果要转换的值不是String，那么就不转换了，直接返回
                return value;
            }
            String val = (String) value;//把值转换成String

            // 使用SimpleDateFormat进行转换
            SimpleDateFormat sdf = new SimpleDateFormat("yyyy-MM-dd");
            try {
                return sdf.parse(val);
            } catch (ParseException e) {
                throw new RuntimeException(e);
            }
        }
    }
}

BaseServlet

public class BaseServlet extends HttpServlet {

    @Override
    public void service(HttpServletRequest request, HttpServletResponse response) throws ServletException, IOException {
        response.setContentType("text/html;charset=UTF-8");//处理响应编码

        String methodName = request.getParameter("method");
        Method method = null;
        try {
            method = this.getClass().getMethod(methodName, HttpServletRequest.class, HttpServletResponse.class);
        } catch (Exception e) {
            throw new RuntimeException("您要调用的方法：" + methodName + "它不存在！", e);
        }
        
        try {
            String result = (String) method.invoke(this, request, response);
            if (result != null && !result.trim().isEmpty()) {//如果请求处理方法返回不为空
                if (result.startsWith("f:")) {
                    request.getRequestDispatcher(result.replaceFirst("f:", "")).forward(request, response);
                } else if (result.startsWith("r:")) {
                    response.sendRedirect(request.getContextPath() + result.replaceFirst("d:", ""));
                } else {
                    response.getWriter().write(result);
                }
            }
        } catch (Exception e) {
            throw new RuntimeException(e);
        }
    }

    protected void startPage(HttpServletRequest request) {
        int pageNum = getParameterToInt(request, "pageNum", 0);
        int pageSize = getParameterToInt(request, "pageSize", 10);
        PageHelper.startPage(pageNum, pageSize);
    }

    private int getParameterToInt(HttpServletRequest request, String key, int defaultValue) {
        int value = defaultValue;
        String param = request.getParameter(key);
        if (param != null && !param.trim().isEmpty()) {
            try {
                value = Integer.parseInt(param);
            } catch (Exception ignore) {}
        }
        return value;
    }
}