Multiple Type Parameters : Generic Parameters

class Pair<KeyType, ValueType> {
  // Constructor
  public Pair(KeyType aKey, ValueType aValue) {
    key = aKey;
    value = aValue;
  }

  // Get the key for this pair
  public KeyType getKey() {
    return key;
  }

  // Get the value for this pair
  public ValueType getValue() {
    return value;
  }

  // Set the value for this pair
  public void setValue(ValueType aValue) {
    value = aValue;
  }

  private KeyType key;

  private ValueType value;
}

public class MainClass {

  public static void main(String[] a) {
    Pair<Integer, String> p = new Pair<Integer, String>(1, "A");

    System.out.println(p.getKey().getClass().getName());
  }
}
java.lang.Integer

  

时间: 2024-11-05 22:35:01

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