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Will null-assigning help GC ?

https://blog.csdn.net/dfdsggdgg/article/details/52463882

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Follow the Above Test

• My JDK Version: 1.8.0_152
• My VM Options: -Xmx5M

import java.util.ArrayList;
import java.util.List;

public class Test {
    public static void main(String[] args) {
        boolean willAssignNull = true;

        List<String> list = new ArrayList<>();
        for (int i = 0; i < 100000; i++) {
            String a = new String("aaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaa");
            list.add(a);
        }
        if (willAssignNull) {
            list = null;
        }

        List<String> list2 = new ArrayList<>();
        for (int i = 0; i < 100000; i++) {
            String a = new String("aaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaa");
            list2.add(a);
        }
        if (willAssignNull) {
            list2 = null;
        }

        List<String> list3 = new ArrayList<>();
        for (int i = 0; i < 100000; i++) {
            String a = new String("aaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaa");
            list3.add(a);
        }
        if (willAssignNull) {
            list3 = null;
        }

        List<String> list4 = new ArrayList<>();
        for (int i = 0; i < 100000; i++) {
            String a = new String("aaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaa");
            list4.add(a);
        }
        if (willAssignNull) {
            list4 = null;
        }

        List<String> list5 = new ArrayList<>();
        for (int i = 0; i < 100000; i++) {
            String a = new String("aaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaa");
            list5.add(a);
        }
        if (willAssignNull) {
            list5 = null;
        }
    }
}

Summary

Yes, it’s true.

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