Freemarker:方便地生成 UUID [英] Freemarker: generate UUID conveniently

问题描述

Freemarker 中似乎没有方便的内置功能来在模板中生成随机 UUID.

我能想到的最好方法是创建一个 Freemarker 方法；在我的 Java 8 代码中，我注入了该方法以供以后在模板中使用.示例:

public String generate(Map data, String templateLocation) throws IOException, TemplateException {尝试 (StringWriter writer = new StringWriter()) {模板模板 = configuration.getTemplate(templateLocation);//在这一行注入的 UUID 生成方法:data.put("uuid", (TemplateMethodModelEx) (list) -> UUID.randomUUID());模板.过程(数据，作家)；返回 writer.toString();}}

在 Freemarker 模板中，我可以使用如下方法:

${uuid()}

在 Freemarker 中生成 uuid 是否有更方便的解决方案?

这是我的 Maven 依赖项:

<依赖><groupId>org.freemarker</groupId><artifactId>freemarker</artifactId><version>2.3.25-incubating</version><范围>测试</范围></依赖>

解决方案

您可以使用 statics 在模板中调用 randomUUID:

${statics["java.util.UUID"].randomUUID()}

<块引用>

如果该对象用作以类名作为键的散列，则该对象几乎公开任何类的静态方法.

There seems to be no convenient built-in in Freemarker to generate a random UUID in a template.

The best I could come up with was by creating a Freemarker method; in my Java 8 code I inject the method for later usage in the template. Example:

public String generate(Map<String, Object> data, String templateLocation) throws IOException, TemplateException {
    try (StringWriter writer = new StringWriter()) {
        Template template = configuration.getTemplate(templateLocation);
        // UUID generation method injected in this line:
        data.put("uuid", (TemplateMethodModelEx) (list) -> UUID.randomUUID());
        template.process(data, writer);
        return writer.toString();
    }
}

In the Freemarker template I can then use the method like this:

${uuid()}

Is there a more convenient solution to generate uuids in Freemarker?

Here is the my Maven dependency:

<dependency>
    <groupId>org.freemarker</groupId>
    <artifactId>freemarker</artifactId>
    <version>2.3.25-incubating</version>
    <scope>test</scope>
</dependency>

解决方案

You can use statics to call randomUUID in your template:

${statics["java.util.UUID"].randomUUID()} 

This object exposes just about any class' static methods if it's used as a hash with class name as the key.

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