策略模式的简单实践

背景

为了实现一个根据选择不同的模板进模板内容的替换

新建一个Content.java类,他包含了一个根据模板生成对应的字符窜内容的方法

package com.drink.admin.print.yly;

import com.drink.admin.print.TemplateData;

public interface Content {
    String generateContentByTemplate(TemplateData templateData);
}

新建一个模板的实现类 OneContent.java类

package com.drink.admin.print.yly;

import com.drink.admin.print.TemplateData;
import freemarker.template.Configuration;
import freemarker.template.Template;
import freemarker.template.Version;

import java.io.StringWriter;
import java.util.HashMap;
import java.util.Map;

public class OneContent implements Content {

    @Override
    public String generateContentByTemplate(TemplateData templateData) {
        String ticketTemplateOne = "${template.storeName}\n" +
                "#${template.orderTakeNo}" + "\n" +
                "${template.storeAddress}\r";
        ticketTemplateOne += "餐桌号：${template.orderTableCode}";
        ticketTemplateOne +=
                "订单号：${template.orderNo}\r下单时间：${template.orderTime}\n" +
                        " ———————————————" + "\r" +
                        "收货人：${template.receiveName}\r\r" +
                        "收货地址：${template.receiveAddress}\r\r" +
                        "电话号码：${template.receivePhone}\r\r" +
                        "…………………………………………" + "\r${template.itemContent}\n\n" +
                        "…………………………………………" +
                        "
包装费
￥${template.packFee}
\r" +
                        "
配送费
￥${template.shipFee}
\r" +
                        "
优惠券及活动
-￥${template.activityCouponPrice}
\r" +
                        "
合计
${template.countNumber}
￥${template.realPayPrice}
\r" +
                        "备注： ${template.memo}\r" +
                        "…………………………………………" +
                        "实付金额
￥${template.realPayPrice}
" +
                        "…………………………………………" +
                        "${template.kfQrcode}\r" +
                        "如有问题请联系客服${template.storeTel}";
        StringWriter result = new StringWriter();
        Map templateMap = new HashMap();
        templateMap.put("template", templateData);
        Template template = null;
        try {
            template = new Template("strTpl", ticketTemplateOne, new Configuration(new Version("2.3.23")));
            template.process(templateMap, result);
        } catch (Exception e) {
            e.printStackTrace();
        }
        return result.toString();
    }
}

新建一个枚举类，包含了所有的模板相关的信息PrintTemplateEnum.java

package com.drink.admin.print.yly.constant;

import com.drink.admin.print.yly.model.TemplateOneData;
import com.drink.admin.print.yly.model.TemplateTwoData;
import freemarker.template.Configuration;
import freemarker.template.Template;
import freemarker.template.Version;

import java.io.StringWriter;
import java.util.HashMap;
import java.util.Map;

import static com.drink.admin.print.yly.constant.YlyTemplate.*;


/**
 * @author xu
 */

public enum PrintTemplateEnum {
    /**
     * 模板一 打印小票
     */
    TEMPLATE_ONE(1, new OneContent());
    private Integer code;
    private Content content;

    PrintTemplateEnum(int code, Content content) {
        this.code = code;
        this.content = content;
    }

    public Integer getCode() {
        return code;
    }

    public Content getContent() {
        return content;
    }

}

测试调用

    public static void main(String[] args) {
        TemplateData templateData = new TemplateData();
        // 选中对应的内容
        for (PrintTemplateEnum value : PrintTemplateEnum.values()) {
            if (value.getCode().equals(1)) {
                Content content = value.getContent();
                String s = content.generateContentByTemplate(templateData);
                System.out.println(s);
            }
        }
    }