lang

Orthodox OOP constructions of extensive use that we need badly in all our projects.

Currently contains java.util.function extensions CachingFunction and CachingSupplier who look like Function and Supplier correspondingly, but encapsulate caching behaviour.

how to use

dependency

The library is published on jcenter. To apply to, say, gradle build, use

repositories {
    jcenter()
}

dependencies {
    implementation group: 'ru.arsysop.lang', name: 'lang', version: '0.1'
}

or have a hint for your build automation system.

code

Here is the sample of CachingFunction usage. It

• does not perform any calculations in ctor
• does not contain not-final fields
• calculates lazily
• and do it only ones for the first need

public final class UserFromEmail {

	private final CachingFunction<String, String> name;

	/**
	 * Get the first part of an email address (before '@'-symbol) as a user name.
	 *
	 * @param email valid email address
	 */
	public UserFromEmail(String email) {
		name = new CachingFunction<>(email, input -> input.substring(0, input.indexOf('@')));
	}

	public String name() {
		return name.get();
	}

}