将array_walk从php转换为java方法

Question

There is a function in PHP like this

function array_walk(array &$array, callable $callback, $userdata = null): bool {}

I want to use this method in Java. Can anyone help me?

For example, I want to convert this function to Java

array_walk($result, function (&$value, $key) {
    $value = sprintf('%s/%s', $key, $value);
});

Answer 1

I have searched out what does this method do at W3C and I can clearly say that for this purpose the Java 8 Stream API takes the place using the forEach():

String[] a = {"blue", "red"};
Stream.of(a).forEach(i -> System.out.println("This is a " + i + " color."));

Results in:

This is a blue color.
This is a red color.

You can also implement your one which does exactly you want using @FunctionalInterface. However you cannnot use it since you are stucked in Java 7 and earlier. In this case you have to use the ordinary for-loop or the very own class and @Override the implementation:

public class ArrayWalker<T> {

    T[] t;

    public ArrayWalker(T[] t) {
        this.t = t; 
    }

    public void function(T t) {}

    public ArrayWalker<T> walk() {
        for (int i=0; i<t.length; i++) {
            function(t[i]);
        }
        return this;
    }
}

Usage:

new ArrayWalker<String>(array) {
    @Override
    public void function(String str) {
        System.out.println("This is a " + str + " color.");
    }
}.walk();

It will result in the same output as the example above.