Thymeleaf If-Not-Null Dialect

A dialect that outputs elements and values only if the value exist. It's basically a combination of th:if with the underlying Thymeleaf processor it mimics, eg: ifnotnull:text = th:if + th:text.

Installation

Minimum of Java 8 and Thymeleaf 3.0 required.

For Maven and Maven-compatible dependency managers

Add a dependency to your project with the following co-ordinates:

• GroupId: nz.net.ultraq.thymeleaf
• ArtifactId: thymeleaf-ifnotnull-dialect
• Version: 4.1.0

Check the project releases for a list of available versions. Each release page also includes a downloadable JAR if you want to manually add it to your project classpath.

Usage

Configure Thymeleaf to include the if-not-null dialect using one of the methods below:

• Spring or Spring Boot 2 w/ Java/annotation config:

  @Bean
  public IfNotNullDialect ifNotNullDialect() {
    return new IfNotNullDialect();
  }

• DIY management of the Thymeleaf template engine:

  TemplateEngine templateEngine = new TemplateEngine();
  templateEngine.addDialect(new IfNotNullDialect());

This will introduce the ifnotnull namepace, and some new attribute processors that you can use in your pages, outlined below:

src

A combination of th:if and th:src, runs the expression given to it and, if it's not null, outputs the element and the result of the expression to the src attribute of the element.

<img ifnotnull:src="${myObject.imageUrl}"/>

text

A combination of th:if and th:text, runs the expression given to it and, if it's not null, outputs both the element and the result of the expression as a text node of the element.

<div ifnotnull:text="${myObject.someProperty}"></div>

utext

Same as above, but prints unescaped text instead.

<div ifnotnull:utext="${myObject.someProperty}"></div>