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Missing method body, or declare abstract in Java

Remove the semicolon on the end of this line: public static void helloWorld();

Web server failed to start. Port 8080 was already in use. Spring Boot microservice

If you don’t want the embedded server to start, just set the following property in you application.properties (or .yml): If your classpath contains the necessary bits to start a web server, Spring Boot will automatically start it. To disable this behaviour configure the WebApplicationType in your application.properties Source: https://docs.spring.io/spring-boot/docs/current/reference/html/howto-embedded-web-servers.html If you application really is a Web application, then you can easily … Read more

How to sort an array of objects in Java?

You have two ways to do that, both use the Arrays utility class Implement a Comparator and pass your array along with the comparator to the sort method which take it as second parameter. Implement the Comparable interface in the class your objects are from and pass your array to the sort method which takes only one parameter. Example Output

Android – SPAN_EXCLUSIVE_EXCLUSIVE spans cannot have a zero length

I have run into the same error entries in LogCat. In my case it’s caused by the 3rd party keyboard I am using. When I change it back to Android keyboard, the error entry does not show up any more.

Could not resolve placeholder in string value

In your configuration you have 2 PropertySourcesPlaceholderConfigurer instances. applicationContext.xml infraContext.xml By default a PlaceholderConfigurer is going to fail-fast, so if a placeholder cannot be resolved it will throw an exception. The instance from the applicationContext.xml file has no properties and as such will fail on all placeholders. Solution: Remove the one from applicationContext.xml as it doesn’t add anything it only breaks things.

java code is showing error. ( ‘;’,expected) [closed]

You can’t have statements in the class body (z=x*y;). You have (at least) two options: int z = x * y; use initializer block{ z = x * y; } These are virtually the same. I’d prefer the first option (cleaner) See here

Any implementation of Ordered Set in Java?

Take a look at LinkedHashSet class From Java doc: Hash table and linked list implementation of the Set interface, with predictable iteration order. This implementation differs from HashSet in that it maintains a doubly-linked list running through all of its entries. This linked list defines the iteration ordering, which is the order in which elements were inserted into the … Read more