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deepakdeepak
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[QUESTION] wildcards
1 parent 5cf9bad commit ba4593e

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Lines changed: 36 additions & 1 deletion

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‎QUESTIONS.md‎

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}
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```
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47. how to write ?
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```java
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// works
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public class NumberList<E extends Number> extends ArrayList<E>
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// does not work. how to write this
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class UntilNumberList<? extends Number> extends ArrayList<?>
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```
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‎src/main/Foo.java‎

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package main;
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public interface Foo {
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public void process();
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}

‎src/main/Main.java‎

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import java.util.ArrayList;
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import java.util.Arrays;
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import java.util.List;
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public class Main {
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System.out.println("number list: " + rawNumberList);
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}
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class PersonFoo extends Person implements Foo {
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public PersonFoo(String name) {
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super(name);
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}
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@Override
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public void process() {
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}
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}
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public static void process(List<? extends Foo> list) {
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for (Foo elem : list) {
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}
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}
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public static <T extends Comparable<T>> int countGreaterThan(T[] anArray, T x) {
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int count = 0;
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‎src/main/NumberList.java‎

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public Stream<E> stream() {
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return null;
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}
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}
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}
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// how to write this
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// class UntilNumberList<? extends Number> extends ArrayList<?>

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