Thymeleaf dropdown with selected option

Thymeleaf suggests dropdown creation as follows:

<select th:field="*{type}">
<option th:each="type : ${allTypes}"
             th:value="${type}"
             th:text="#{${'seedstarter.type.' + type}}">Wireframe
</option>
</select>

However, if you want to have a 'selected' option this would not work:

<select th:field="*{type}">
 <option th:each="type : ${allTypes}"
              th:value="${type}"
              th:text="#{${'seedstarter.type.' + type}}"
              th:selected="${myCondition}">Wireframe
</option>
</select>

Instead you should do:

<select name="type">
<option th:each="type : ${allTypes}"
             th:value="${type}"
             th:text="#{${'seedstarter.type.' + type}}"
             th:selected="${myCondition}">Wireframe
</option>
</select>

Sending custom cookies with Postman

To send a custom cookie with Postman (API testing tool), set a "Cookie" header with value similar to "name=value". For example, to send JSESSIONID='Babis' include this header:

Header Key | Header Value
Cookie | JSESSIONID='Babis'

 As described here, you should first install Postman's interceptor extension.

Adding a new non-null column in a JPA entity with default value (on schema upgrade)

Say you have the following table:

Id | First | Last | Phone
1 Thoring Oakenshield 123456
2 Bilbo Baggins 654321

...and you want to add an extra Email column which should be non-null and default to email@email.com (without losing any data).

In you JPA entity, write:

@Column(nullable = false, columnDefinition = "Varchar(255) default 'email@email.com'")
private String email;
// getter + setter

Make sure you have these external properties set in application.properties:

• spring.jpa.generate-ddl
• spring.jpa.hibernate.ddl-auto

Read here for more details.

Also, keep in mind that this is not safe. Not to be used in production. Related stackoverflow discussion.

Tested this with
spring-boot-starter-data-jpa:1.3.1 and Oracle Database 11g Express Edition Release 11.2.0.2.0.

Sequence of characters separated by a delimiter and optionally starting with a supplied prefix and ending with a supplied suffix

If you have an array of Strings, say ["9", "30", "0"], and you wish to convert it to a String "[9, 30, 0]", do:

StringJoiner sj = new StringJoiner(",", "[", "]");
Arrays.asList(myArray).forEach(p -> sj.add(p));
sj.toString();

More about StringJoiner:
https://docs.oracle.com/javase/8/docs/api/java/util/StringJoiner.html