Hamcrest matcher that matches a Lambda.

LambdaMatcher.java

import java.util.function.Function;

import org.hamcrest.BaseMatcher;
import org.hamcrest.Description;

public class LambdaMatcher<T> extends BaseMatcher<T>
{
    private final Function<T, Boolean> matcher;
    private final String description;

    public LambdaMatcher(Function<T, Boolean> matcher,
                         String description)
    {
        this.matcher = matcher;
        this.description = description;
    }

    @Override
    public boolean matches(Object argument)
    {
        return matcher.apply((T) argument);
    }

    @Override
    public void describeTo(Description description)
    {
        description.appendText(this.description);
    }
}

This looks awesome! Can you show an example use case? I'm not sure how and where to plug in this matcher. Thanks!

assertThat(collection,hasItem(new LambdaMatcher(a -> a.getStr1().equals("abc"),"Str1 should equal Abc")));

vs

 assertThat(collection.stream().map(a -> a.getStr1()).collect(toList()),hasItem(equalTo("abc")));