Spring SpEL - Expression Templating


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SpEL expression allows to mix literal text with evaluation block(s). Each evaluation block is to be prefixed and suffixed properly. Standard choice is to use #{}. org.springframework.expression.common. TemplateParserContextTemplateParserContext uses the same.

Syntax

String result = parser.parseExpression("Random number : #{T(java.lang.Math).random() 
   * 100}", new TemplateParserContext()).getValue(String.class);

Following example shows the various use cases.

Example

Let's update the project created in Spring SpEL - Create Project chapter. We're adding/updating following files −

  • MainApp.java − Main application to run and test.

Here is the content of MainApp.java file −

package com.tutorialspoint;

import java.text.ParseException;
import org.springframework.expression.ExpressionParser;
import org.springframework.expression.common.TemplateParserContext;
import org.springframework.expression.spel.standard.SpelExpressionParser;

public class MainApp {
   public static void main(String[] args) throws ParseException, NoSuchMethodException, SecurityException {
      ExpressionParser parser = new SpelExpressionParser();
      String result=parser.parseExpression("Random number : #{T(java.lang.Math).random() 
         * 100}", new TemplateParserContext()).getValue(String.class);
      System.out.println(result);
   }
}

Output

Random number : 18.056323318070998
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