Using #else directive, we can specify what to do when the condition in #if directive is evaluated to false.
Syntax
<#if condition>
...
<#else>
...
</#if>
welcome.ftl
<#if user.gender == "Male">
Welcome Mr. ${user.name}
<#else>
Welcome Madam. ${user.name}
</#if>
Step 1: Define Model class ‘WelcomeUser’.
WelcomeUser.java
package com.sample.app.templates.model;
public class WelcomeUser {
private String name;
private String gender;
public WelcomeUser(String user, String gender) {
super();
this.name = user;
this.gender = gender;
}
public String getName() {
return name;
}
public void setName(String name) {
this.name = name;
}
public String getGender() {
return gender;
}
public void setGender(String gender) {
this.gender = gender;
}
}
Step 2: Define ‘FreeMarkerUtil’ class that take model class and template file as input and merge them.
FreeMarkerUtil.java
package com.sample.app.util;
import java.io.StringWriter;
import java.util.Locale;
import freemarker.template.Configuration;
import freemarker.template.Template;
import freemarker.template.TemplateExceptionHandler;
public class FreeMarkerUtil {
private static final Configuration FREE_MARKER_CONFIGURATION = new Configuration(Configuration.VERSION_2_3_30);
static {
FREE_MARKER_CONFIGURATION.setClassForTemplateLoading(FreeMarkerUtil.class, "/templates/");
FREE_MARKER_CONFIGURATION.setDefaultEncoding("UTF-8");
FREE_MARKER_CONFIGURATION.setLocale(Locale.US);
FREE_MARKER_CONFIGURATION.setTemplateExceptionHandler(TemplateExceptionHandler.RETHROW_HANDLER);
}
public static StringWriter mergeModelAndTemplate(Object modelObject, String ftlFile) throws Exception {
StringWriter stringWriter = new StringWriter();
Template template = FREE_MARKER_CONFIGURATION.getTemplate(ftlFile);
template.process(modelObject, stringWriter);
return stringWriter;
}
}
Step 3: Define ‘WelcomeUserPopulator’.
WelcomeUserPopulator.java
package com.sample.app;
import java.io.StringWriter;
import java.util.HashMap;
import java.util.Map;
import com.sample.app.templates.model.WelcomeUser;
import com.sample.app.util.FreeMarkerUtil;
public class WelcomeUserPopulator {
public static void main(String args[]) throws Exception {
Map<String, Object> modelObject = new HashMap<String, Object>();
modelObject.put("user", new WelcomeUser("Krishna", "Male"));
StringWriter stringWriter = FreeMarkerUtil.mergeModelAndTemplate(modelObject, "welcome.ftl");
System.out.println(stringWriter.toString().trim());
modelObject.put("user", new WelcomeUser("Sailu", "Female"));
stringWriter = FreeMarkerUtil.mergeModelAndTemplate(modelObject, "greet.ftl");
System.out.println(stringWriter.toString().trim());
}
}
Output
Welcome Mr. Krishna
Welcome Madam. Sailu
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