Java程序从HashMap中删除键值对？

Java Program to remove key value pair from HashMap?

假设以下是我们的HashMap-

1	HashMap<String, String>map = new HashMap<String, String>();

将键值对添加到HashMap-

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map.put("1","A");
map.put("2","B");
map.put("3","C");
map.put("4","D");
map.put("5","E");
map.put("6","F");
map.put("7","G");
map.put("8","H");
map.put("9","I");

现在，使用remove()方法删除键值对-

1	map.remove("5");

例

现场演示

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import java.util.Collection;
import java.util.HashMap;
import java.util.Iterator;
import java.util.LinkedHashMap;
import java.util.Map;
import java.util.Set;
public class Demo {
public static void main(String[] args) {
HashMap<String, String>map = new HashMap<String, String>();
map.put("1","A");
map.put("2","B");
map.put("3","C");
map.put("4","D");
map.put("5","E");
map.put("6","F");
map.put("7","G");
map.put("8","H");
map.put("9","I");
System.out.println("HashMap...");
for (String res: map.keySet()) {
System.out.println(res);
}
map.remove("5");
System.out.println("Updated HashMap...");
for (String res: map.keySet()) {
System.out.println(res);
}
map.remove("8");
System.out.println("Updated HashMap...");
for (String res: map.keySet()) {
System.out.println(res);
}
}
}

输出量

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HashMap...
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Updated HashMap...
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Updated HashMap...
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