53 lines
1.2 KiB
Markdown
53 lines
1.2 KiB
Markdown
+++
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title = "dynamica"
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draft = false
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tags = [
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"",
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"Users",
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"jefklak",
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"Downloads",
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"pages",
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"code",
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"java",
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"dynamica"
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]
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date = "2013-03-12"
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+++
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# Dynamica
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Hier zitten stukjes code om java meer dynamiek te geven (voorzover dat mogelijk is...)
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Veel collectie gerelateerde dingen (`filter`, `map` etc) is reeds geïmplementeerd: http://code.google.com/p/guava-libraries/
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### Reduce met optellen
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```java
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public class CollectionUtil {
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public static interface EnkelvoudigeTeller<TellerType> {
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boolean magMeegeteldWorden(TellerType object);
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}
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public static interface MeervoudigeTeller<TellerType> {
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int geefAantalMeegeteld(TellerType object);
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}
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public static <TellerType> int tel(Collection<TellerType> objecten, MeervoudigeTeller<TellerType> teller) {
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int geteld = 0;
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for (TellerType object : objecten) {
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geteld += teller.geefAantalMeegeteld(object);
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}
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return geteld;
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}
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public static <TellerType> int tel(Collection<TellerType> objecten, final EnkelvoudigeTeller<TellerType> teller) {
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return tel(objecten, new MeervoudigeTeller<TellerType>() {
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@Override
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public int geefAantalMeegeteld(TellerType object) {
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return teller.magMeegeteldWorden(object) ? 1 : 0;
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}
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});
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}
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}
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``` |