我这里有一个例子:
import java.lang.ref.WeakReference;
public class WeakRefTest {
public static void main(String[] args) {
Object obj = new Object();
WeakReference<Object> weakRef = new WeakReference<Object>(obj);
int i = 0;
while (true) {
if (weakRef.get() != null) {
i++;
System.out.println("The object is alive for " + i + " loops - " + weakRef);
} else {
System.out.println("The object has been collected.");
break;
}
}
}
}
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运行这个程序时,我们会"The object has been collected."在一段时间后得到输出,这意味着对象将被 gc-ed。
但是,仍然存在一个名为"obj"链接到对象的强引用,如何回收?因为后来JVM发现没有强引用使用,所以不是强可达?