Thymeleaf 3.0 自定义标签方言属性的实例讲解

此篇文章内容仅限于 描述 thy3.0 自定义标签的说明，所以你在看之前，请先会使用它。

直奔主题，以下代码是如何引用 第三方标签的。说明： shrioDialect 是Shiro 官方为thy开发的自定义标签工具。和jsp的一样

RiskDialect 是我写的自定义标签

 <bean id="templateEngine" class="org.thymeleaf.spring3.SpringTemplateEngine">
     <property name="templateResolver" ref="templateResolver"/>
     <property name="additionalDialects">
    <set>
      <!-- thymeleaf 使用shiro标签 -->
     <bean class="at.pollux.thymeleaf.shiro.dialect.ShiroDialect"/>
     <bean class="com.hpay.risk.boss.common.RiskDialect"/>
    </set>
  </property>
 </bean>

首先看代码：

import java.util.LinkedHashSet;
import java.util.Set;
import org.thymeleaf.dialect.AbstractProcessorDialect;
import org.thymeleaf.processor.IProcessor;
import org.thymeleaf.standard.StandardDialect;

/**
 *@author Garc
 *@Date 2017年2月16日 上午11:42:51
 *@info thymeleaf 自定义标签属性
 *@snise
 **/
public class RiskDialect extends AbstractProcessorDialect {

  private static final String NAME = "Risk";
  private static final String PREFIX = "risk";

  public RiskDialect() {
    super(NAME, PREFIX, StandardDialect.PROCESSOR_PRECEDENCE);
  }

 @Override
 public Set<IProcessor> getProcessors(String dialectPrefix) {
 return createStandardProcessorsSet(dialectPrefix);
 }

 private Set<IProcessor> createStandardProcessorsSet(String dialectPrefix) {
 LinkedHashSet<IProcessor> processors = new LinkedHashSet<IProcessor>();
 processors.add(new SansitiveEncryptProcessor(dialectPrefix));
 return processors;
 }

}

我定义了 RiskDialect 类，并需要继承 thymeleaf 官方 方言类

我定义的这个是为了做敏感数据加密用的。 这是前段代码。

以下是实现自定义标签方言 代码：

import static at.pollux.thymeleaf.shiro.processor.ThymeleafFacade.evaluateAsStringsWithDelimiter;
import static at.pollux.thymeleaf.shiro.processor.ThymeleafFacade.getRawValue;

import java.util.List;
import org.thymeleaf.context.ITemplateContext;
import org.thymeleaf.engine.AttributeName;
import org.thymeleaf.model.IModel;
import org.thymeleaf.model.IModelFactory;
import org.thymeleaf.model.IProcessableElementTag;
import org.thymeleaf.processor.element.AbstractAttributeTagProcessor;
import org.thymeleaf.processor.element.IElementTagStructureHandler;
import org.thymeleaf.templatemode.TemplateMode;
import org.unbescape.html.HtmlEscape;

import com.hpay.utils.StringUtils;

/**
 *@author Garc
 *@Date 2017年2月16日 上午11:48:34
 *@info 敏感加密标签
 *@snise
 **/
public class SansitiveEncryptProcessor extends AbstractAttributeTagProcessor{

  private static final String DELIMITER = ",";
  private static final String ATTRIBUTE_NAME = "sansiEncrypt";
  private static final int PRECEDENCE = 300;

  private static final String CARD="card";
  private static final String MOBILE="mobile";
  private static final String IDENTITY="identity";
  private static final String CSN="csn";

 protected SansitiveEncryptProcessor( String dialectPrefix) {
 super(
        TemplateMode.HTML, // 处理thymeleaf 的模型
        dialectPrefix, // 标签前缀名
        null, // No tag name: match any tag name
        false, // No prefix to be applied to tag name
        ATTRIBUTE_NAME, // 标签前缀的 属性 例如：< risk:sansiEncrypt="">
        true, // Apply dialect prefix to attribute name
        PRECEDENCE, // Precedence (inside dialect's precedence)
        true); // Remove the matched attribute afterwards
    }

 @Override
 protected void doProcess(ITemplateContext context,
  IProcessableElementTag tag, AttributeName attributeName,
  String attributeValue, IElementTagStructureHandler structureHandler) {

        final String rawValue = getRawValue(tag, attributeName); //获取标签内容表达式
 String type=null;
 String exper=null;
 if(StringUtils.isNotBlank(rawValue)){
  type=rawValue.split(":")[0]; //获取类型
  exper=rawValue.split(":")[1]; //获取表达式
 }
 //通过IStandardExpression 解析器 解析表达式获取参数
     final List<String> values = evaluateAsStringsWithDelimiter(context, exper, DELIMITER);
     final String elementCompleteName = tag.getElementCompleteName(); //标签名
     //创建模型
     final IModelFactory modelFactory = context.getModelFactory();
     final IModel model = modelFactory.createModel();
     //添加模型 标签
     model.add(modelFactory.createOpenElementTag(elementCompleteName));
     for (String value : values) {
     //创建 html5标签 文本返回数据
     if(CARD.equals(type)){
      model.add(modelFactory.createText(HtmlEscape.escapeHtml5(getCardNo(value))));
     }else if(MOBILE.equals(type)){
      model.add(modelFactory.createText(HtmlEscape.escapeHtml5(getMobile(value))));
     }else if(IDENTITY.equals(type)){
      model.add(modelFactory.createText(HtmlEscape.escapeHtml5(getIdentity(value))));
     }else if(CSN.equals(type)){
      model.add(modelFactory.createText(HtmlEscape.escapeHtml5(getCsn(value))));
     }
  }
     //添加模型 标签
     model.add(modelFactory.createCloseElementTag(elementCompleteName));
     //替换页面标签
     structureHandler.replaceWith(model, false);
 }

 protected String getCardNo(String cardNo) {
 if (StringUtils.isNotBlank(cardNo) && cardNo.length() >= 9) {
  return cardNo.substring(0, 4) + cardNo.substring(4, cardNo.length() - 3).replaceAll("[0-9]", "*") + cardNo.substring(cardNo.length() - 4, cardNo.length());
 }
 return cardNo;
 }

    protected static String getIdentity(String val){
       if(org.apache.commons.lang.StringUtils.isBlank(val)||val.length()<9){
 return val;
     }else{
     return val.substring(0, 4)+ val.substring(4, val.length()-4).replaceAll("[0-9]", "*") + val.substring(val.length()-4, val.length());
     }
    }
  /**
   * 前四后四显示
   * @param val
   * @return
   */
  protected static String getMobile(String val){
 if(org.apache.commons.lang.StringUtils.isBlank(val)||val.length()<9){
  return val;
   }else{
   return val.substring(0, 3)+ val.substring(4, val.length()-3).replaceAll("[0-9]", "*") + val.substring(val.length()-4, val.length());
   }
 }
  /**
   * 星星显示
   * @param val
   * @return
   */
  protected String getCsn(String val){
 if(org.apache.commons.lang.StringUtils.isBlank(val)||val.length()<12){
   return val;
   }else{
   return val.substring(0, 2)+ val.substring(2, val.length()-3).replaceAll("[0-9a-zA-Z]", "*") + val.substring(val.length()-6, val.length());
   }
   }
}

以下代码是为了向SansitiveEncryptProcessor 提供的解析表达式 thymeleaf解析器，用来获取参数值的：

import org.thymeleaf.context.ITemplateContext;
import org.thymeleaf.engine.AttributeName;
import org.thymeleaf.exceptions.TemplateProcessingException;
import org.thymeleaf.model.IProcessableElementTag;
import org.thymeleaf.standard.expression.IStandardExpression;
import org.thymeleaf.standard.expression.IStandardExpressionParser;
import org.thymeleaf.standard.expression.StandardExpressionParser;
import org.thymeleaf.util.EvaluationUtils;
import org.thymeleaf.util.StringUtils;

import java.util.ArrayList;
import java.util.List;

import static java.util.Arrays.asList;
import static java.util.Collections.unmodifiableList;
import static org.thymeleaf.util.StringUtils.trim;
import static org.thymeleaf.util.Validate.notEmpty;
import static org.thymeleaf.util.Validate.notNull;

public final class ThymeleafFacade {

  private ThymeleafFacade() {
    throw new UnsupportedOperationException();
  }

  public static String getRawValue(final IProcessableElementTag element, final AttributeName attributeName) {
    notNull(element, "element must not be null");
    notNull(attributeName, "attributeName must not be empty");

    final String rawValue = trim(element.getAttributeValue(attributeName));
    notEmpty(rawValue, "value of '" + attributeName + "' must not be empty");

    return rawValue;
  }

  public static String getRawValue(final IProcessableElementTag element, final String attributeName) {
    notNull(element, "element must not be null");
    notEmpty(attributeName, "attributeName must not be empty");

    final String rawValue = trim(element.getAttributeValue(attributeName));
    notEmpty(rawValue, "value of '" + attributeName + "' must not be empty");

    return rawValue;
  }

  public static Object evaluateExpression(ITemplateContext arguments, String expression) throws TemplateProcessingException {
    notNull(arguments, "arguments must not be null");
    notEmpty(expression, "expression must not be empty");

    final IStandardExpressionParser parser = new StandardExpressionParser();

    final IStandardExpression evaluableExpression = parser.parseExpression(arguments, expression);

    return evaluableExpression.execute(arguments);
  }

  public static List<Object> evaluateAsIterable(ITemplateContext arguments, String rawValue) throws TemplateProcessingException {
    notNull(arguments, "arguments must not be null");
    notEmpty(rawValue, "rawValue must not be empty");

    final Object evaluatedExpression = evaluateExpression(arguments, rawValue);

    return EvaluationUtils.evaluateAsList(evaluatedExpression);
  }

  public static List<Object> evaluateAsIterableOrRawValue(ITemplateContext arguments, String rawValue) {
    notNull(arguments, "arguments must not be null");
    notEmpty(rawValue, "rawValue must not be empty");

    final List<Object> result = new ArrayList<Object>();
    try {
      result.addAll(evaluateAsIterable(arguments, rawValue));
    } catch (TemplateProcessingException ex) {
      result.add(rawValue);
    }

    return unmodifiableList(result);
  }

  public static List<String> evaluateAsStringsWithDelimiter(ITemplateContext arguments, String rawValue, String delimiter) {
    notNull(arguments, "arguments must not be null");
    notEmpty(rawValue, "rawValue must not be empty");
    notEmpty(delimiter, "delimiter must not be empty");

    final List<String> result = new ArrayList<String>();
    final List<Object> iterates = evaluateAsIterableOrRawValue(arguments, rawValue);

    for (Object o : iterates) {
      result.addAll(asList(StringUtils.split(o, delimiter)));
    }

    return unmodifiableList(result);
  }

以上为 后端代码实现内容，

页面标签使用方式：

<td risk:sansiEncrypt="card:${data.payerCardNo}"></td>

card 是需要 加密的类型，我实现的代码里 对身份证和 手机号还有 CSN 加了密。

上面的内容讲的是 标签传入数据 并返回处理数据。

类似于 if 的标签属性，就不写了。

以上这篇Thymeleaf 3.0 自定义标签方言属性的实例讲解就是小编分享给大家的全部内容了，希望能给大家一个参考，也希望大家多多支持我们。