SpringBoot配置FreeMarker模板

package com.study.configs;

import cn.org.rapid_framework.freemarker.directive.BlockDirective;
import cn.org.rapid_framework.freemarker.directive.ExtendsDirective;
import cn.org.rapid_framework.freemarker.directive.OverrideDirective;
import org.springframework.beans.factory.annotation.Autowired;
import org.springframework.context.annotation.Configuration;
import org.springframework.web.servlet.view.freemarker.FreeMarkerConfigurer;

import javax.annotation.PostConstruct;

@Configuration
public class FreemarkerConfig {

    @Autowired
    freemarker.template.Configuration configuration;
    @Autowired
    private FreeMarkerConfigurer freeMarkerConfigurer;

    @PostConstruct
    public void setSharedVariable() {
        //freemarker模板继承
        configuration.setSharedVariable("block", new BlockDirective());
        configuration.setSharedVariable("override", new OverrideDirective());
        configuration.setSharedVariable("extends", new ExtendsDirective());
    }
}

FreeMarker Map的key值必须是String类型

官方明确说明了建议使用String类型做为key值，同时注意取值形式

map集合遍历：key代表map的key。
<#list customerType?keys as key >
<option value="${key}">${customerType[key]}</option>
</#list>

List集合遍历

<#list list as item >
	${item.name}
</#list>

freemark 判断内容是否为空

//内容为空时。替代为空字符
${form.getMessageFrom()!''}

//判断是否为空
<#if form.obj??>
不为空时..
<#else>
为空时...
</#if>

freemark 日期转换

${item.lastLoginDate?string("yyyy-MM-dd")}
//空值判断
${(startTime?string("yyyy-MM-dd HH:mm:ss"))!''}

freemark 三元表达式

${(update_name_error??) ? string("has-error","")}

freemarker将数字转换为字符串

${123?c} 结果为123

freemarker将字符串转换数字

${123?number} 字符串123转换为数字123

freemark判断是否包含字符串

${(form.getMessageFrom()!'') ?contains(key) ? string("checked", "") }

freemark自动将多位数数字处理成字符串,以”,”隔开解决

在模板中直接加.toString()转化数字为字符串，如 ${num.toString()}  

* 使用?c控制，如 ${num?c}
* 在freemarker配置文件freemarker.properties(在class目录下即可)加number_format=# 
* 在模板中直接加<#setting number_format="#">;
* 通过freemarker.template.Configuration的config.setNumberFormat("#")来设定freemarker对数值的格式化;

SpringBoot导入支持jsp标签的jar包

<dependency>
   <groupId>commons-lang</groupId>
   <artifactId>commons-lang</artifactId>
   <version>2.6</version>
</dependency>
<dependency>
   <groupId>javax.servlet.jsp</groupId>
   <artifactId>jsp-api</artifactId>
   <version>2.1</version>
</dependency>

freemark使用模板继承,并使用自定义分页标签

package com.study.configs;

import cn.org.rapid_framework.freemarker.directive.BlockDirective;
import cn.org.rapid_framework.freemarker.directive.ExtendsDirective;
import cn.org.rapid_framework.freemarker.directive.OverrideDirective;
import freemarker.ext.jsp.TaglibFactory;
import org.springframework.beans.factory.annotation.Autowired;
import org.springframework.context.annotation.Configuration;
import org.springframework.web.servlet.view.freemarker.FreeMarkerConfigurer;

import javax.annotation.PostConstruct;
import java.util.ArrayList;
import java.util.List;

@Configuration
public class FreemarkerConfig {

    @Autowired
    freemarker.template.Configuration configuration;
    @Autowired
    private FreeMarkerConfigurer freeMarkerConfigurer;

    @PostConstruct
    public void setSharedVariable() {
        //freemarker模板继承
        configuration.setSharedVariable("block", new BlockDirective());
        configuration.setSharedVariable("override", new OverrideDirective());
        configuration.setSharedVariable("extends", new ExtendsDirective());
        //freemarker自定义标签
        List<String> tlds = new ArrayList<>();
        //标签存放的位置
        tlds.add("/static/tags/page.tld");
        TaglibFactory taglibFactory = freeMarkerConfigurer.getTaglibFactory();
        taglibFactory.setClasspathTlds(tlds);
        if (taglibFactory.getObjectWrapper() == null) {
            taglibFactory.setObjectWrapper(freeMarkerConfigurer.getConfiguration().getObjectWrapper());
        }
    }
}

分页标签page.tld

<?xml version="1.0" encoding="UTF-8"?>
<taglib xmlns="http://java.sun.com/xml/ns/j2ee"
		xmlns:xsi="http://www.w3.org/2001/XMLSchema-instance"
		xsi:schemaLocation="http://java.sun.com/xml/ns/j2ee http://java.sun.com/xml/ns/j2ee/web-jsptaglibrary_2_0.xsd"
		version="2.0">
	<description>分页标签</description>
	<tlib-version>1.0</tlib-version>
	<short-name>page</short-name>
	<uri>/page</uri>
	<tag>
		<description>
			用于页面分页的输出
		</description>
		<name>page</name>
		<tag-class>com.hyhb.utils.PageTag</tag-class>
		<body-content>empty</body-content>
		<attribute>
			<description>分页需要的对象</description>
			<name>pagination</name>
			<required>true</required>
			<rtexprvalue>true</rtexprvalue>
		</attribute>
		<attribute>
			<description>是否前端页面</description>
			<name>isWeb</name>
			<required>false</required>
			<rtexprvalue>true</rtexprvalue>
		</attribute>
	</tag>
</taglib>

分页类-PageTag

package com.study.utils;

import javax.servlet.http.HttpServletRequest;
import javax.servlet.jsp.JspException;
import javax.servlet.jsp.JspWriter;
import javax.servlet.jsp.PageContext;
import javax.servlet.jsp.tagext.SimpleTagSupport;
import java.io.IOException;
import java.util.HashMap;
import java.util.Map;

public class PageTag extends SimpleTagSupport {
    private Pagination pagination;
    private boolean isWeb;

    private String getPageUrl(Integer page) {

        HttpServletRequest request = (HttpServletRequest) ((PageContext) this.getJspContext()).getRequest();
        String url = this.pagination.getUrl();
        String queryString = request.getQueryString();
        url = request.getContextPath() + url;
        Map<String, String> params = new HashMap<String, String>();
        params.put("page", page.toString());
        String refactorString = this.pagination.refactorParams(queryString, params);
        if (refactorString.length() > 0) {
            url = url + "?" + refactorString;
        }
        return url;
    }

    private void getDashboardPages(StringBuffer sb) {
        sb.append("<div class='container-fluid' style='position: relative;height: 40px;width: 100%;text-align: center;'>");
        sb.append(String.format("<div style='position: absolute;left: 0;top: 0;width: auto;'>共有 %d 条记录</div>", this.pagination.getTotalCount()));
        sb.append("<ul class='pagination' style='margin: auto;width: auto;'>");
        if (this.pagination.hasPrev()) {
            sb.append(String.format("<li><a href='%s' aria-label='Previous'> <span aria-hidden='true'>&laquo;</span></a></li>", this.getPageUrl(this.pagination.getPage() - 1)));
        } else {
            sb.append("<li class='disabled'><a href='javascript:;' aria-label='Previous'><span aria-hidden='true'>&laquo;</span></a></li>");
        }
        for (Integer page : this.pagination.iteratorPages()) {
            if (page > 0) {
                if (page != this.pagination.getPage()) {
                    sb.append(String.format("<li><a href='%s'>%d</a></li>", this.getPageUrl(page), page));
                } else {
                    sb.append(String.format("<li class='active'><a href='javascript:;'>%d</a></li>", page));
                }
            } else {
                sb.append("<li class='disabled'><a href='javascript:;'>...</a></li>");
            }
        }
        if (this.pagination.hasNext()) {
            sb.append(String.format("<li><a href='%s' aria-label='Previous'> <span aria-hidden='true'>&raquo;</span></a></li>", this.getPageUrl(this.pagination.getPage() + 1)));
        } else {
            sb.append("<li class='disabled'><a href='javascript:;' aria-label='Previous'><span aria-hidden='true'>&raquo;</span></a></li>");
        }
        sb.append("</ul>");
        sb.append("</div>");
    }

    private void getWebPages(StringBuffer sb) {
        sb.append("<div class='Pages'>");
        sb.append("<span class='p_page'>");
        if (this.pagination.getPages() > 0) {
            sb.append(String.format("<a href='%s' class='a_prev'>首页</a>", this.getPageUrl(1)));
        } else {
            sb.append("<a href='javascript:void(0);' class='a_prev'>首页</a>");
        }
        if (this.pagination.hasPrev()) {
            sb.append(String.format("<a href='%s' class='a_prev' style='margin:0 2px;'>上一页</a>", this.getPageUrl(this.pagination.getPage() - 1)));
        } else {
            sb.append("<a href='javascript:void(0);' class='a_prev' style='margin:0 2px;'>上一页</a>");
        }
        sb.append("<em class='num'>");
        for (Integer page :
                this.pagination.iteratorWebPages()) {
            if (page != this.pagination.getPage()) {
                sb.append(String.format("<a href='%s' class='a_num'>%d</a>", this.getPageUrl(page), page));
            } else {
                sb.append(String.format("<a href='javascript:void(0);' class='a_cur'>%d</a>", page));
            }
        }
        sb.append("</em>");
        if (this.pagination.hasNext()) {
            sb.append(String.format("<a href='%s' class='a_next'>下一页</a>", this.getPageUrl(this.pagination.getPage() + 1)));
        } else {
            sb.append("<a href='javascript:void(0);' class='a_next'>下一页</a>");
        }
        sb.append("</span>");
        sb.append("</div>");
    }

    @Override
    public void doTag() throws JspException {
        JspWriter out = this.getJspContext().getOut();//指定输入流，用于页面输出分页信息、

        StringBuffer sb = new StringBuffer();//构建StringBuffer对象，用户拼接分页标签
        if (this.isWeb) {
            getWebPages(sb);
        } else {
            getDashboardPages(sb);
        }
        try {
            out.print(sb.toString());
        } catch (IOException e) {
            e.printStackTrace();
        }
    }

    public Pagination getPagination() {
        return pagination;
    }

    public void setPagination(Pagination pagination) {
        this.pagination = pagination;
    }

    public boolean getIsWeb() {
        return isWeb;
    }

    public void setIsWeb(boolean isWeb) {
        this.isWeb = isWeb;
    }
}

分页实体类-Pagination

package com.study.utils;

import java.util.ArrayList;
import java.util.HashMap;
import java.util.List;
import java.util.Map;

public class Pagination {

    private Integer page;
    private Integer totalCount;
    private Integer pageSize;
    private String url;

    /**
     * 分页公用类
     *
     * @param page       Integer 页数
     * @param pageSize   Integer 页面大小
     * @param totalCount Integer 总数据大小
     * @param url        Integer 分页url
     */
    public Pagination(Integer page, Integer pageSize, Integer totalCount, String url) {
        this.page = page;
        this.pageSize = pageSize;
        this.totalCount = totalCount;
        this.url = url;
    }

    public Integer getPages() {
        return (this.totalCount + this.pageSize - 1) / this.pageSize;
    }

    public Boolean hasPrev() {
        return this.page > 1;
    }

    public Boolean hasNext() {
        return this.page < this.getPages();
    }

    public List<Integer> iteratorPages() {
        Integer leftEdge = 2;
        Integer leftCurrent = 2;
        Integer rightCurrent = 5;
        Integer rightEdge = 2;
        List<Integer> list = new ArrayList<Integer>();
        for (Integer num = 1; num <= this.getPages(); num++) {
            if (num <= leftEdge || (num > this.page - leftCurrent - 1 && num < this.page + rightCurrent) || num > this.getPages() - rightEdge) {
                list.add(num);
            } else {
                if (list.size() > 0 && list.get(list.size() - 1) > 0) {
                    list.add(-1);
                }
            }
        }
        return list;
    }

    public List<Integer> iteratorWebPages() {
        Integer leftEdge = 4;
        Integer rightEdge = 4;
        List<Integer> pages = new ArrayList<>();
        int leftCurrent = 5 - this.page > 0 ? 5 - this.page : 0;
        rightEdge = rightEdge + leftCurrent;
        int rightCurrent = 5 + page > this.getPages() ? 5 + page - this.getPages() : 0;
        leftEdge = leftEdge + rightCurrent;
        for (int num = 1; num <= this.getPages(); num++) {
            if ((num >= page - leftEdge && num <= page + rightEdge)) {
                pages.add(num);
            }
        }
        return pages;
    }

    public String refactorParams(String queryString, Map<String, String> params) {
        Map<String, String> allParams = new HashMap<String, String>();
        if (null != queryString && queryString.length() > 0) {
            String[] paramList = queryString.split("&");
            for (int i = 0; i < paramList.length; i++) {
                String[] key_vale = paramList[i].split("=");
                if (key_vale.length > 1) {
                    allParams.put(key_vale[0], key_vale[1]);
                } else {
                    allParams.put(key_vale[0], "");
                }
            }
        }
        if (null != params) {
            allParams.putAll(params);
        }
        String refactorString = "";
        for (String key : allParams.keySet()) {
            if (refactorString.length() > 0) {
                refactorString += "&";
            }
            refactorString = refactorString + key + "=" + allParams.get(key);
        }
        return refactorString;
    }

    public Integer getPage() {
        return page;
    }

    public void setPage(Integer page) {
        this.page = page;
    }

    public Integer getTotalCount() {
        return totalCount;
    }

    public void setTotalCount(Integer totalCount) {
        this.totalCount = totalCount;
    }

    public Integer getPageSize() {
        return pageSize;
    }

    public void setPageSize(Integer pageSize) {
        this.pageSize = pageSize;
    }

    public String getUrl() {
        return url;
    }

    public void setUrl(String url) {
        this.url = url;
    }

    public static void main(String[] args) {
        Pagination pagination = new Pagination(8, 20, 4000, "");
        Map<String, String> params = new HashMap<String, String>();
        params.put("param1", "param1");
        params.put("param2", "param2");
        String refactorString = pagination.refactorParams("param1=1&param3=", params);
        System.out.println(refactorString);
    }
}

freemark页面中使用分页标签

页面头部导入标签

<#assign page = JspTaglibs["/page"] />

在需要分页的地方使用-后端

<@page.page pagination=pagination/>

如果是前端

<@page.page pagination=pagination isWeb=true/>
原文链接: https://marshucheng1.github.io/2017/03/03/javaweb-FreeMarker/