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JDI:如何迭代 HashMap

[英]JDI:How to iterate over HashMap

I get through JDI to get com.sun.jdi.ObjectReference is type java.util.HashMap ,then i get filed value "entrySet",why it is always null? I get through JDI to get com.sun.jdi.ObjectReference is type java.util.HashMap ,then i get filed value "entrySet",why it is always null? How can i iterate over HashMap keyValues with java debug api?如何使用 java 调试 api 迭代 HashMap 键值?

public static void displayVariables(LocatableEvent event) throws IncompatibleThreadStateException, AbsentInformationException {
        StackFrame stackFrame = event.thread().frame(0);
        for (LocalVariable visibleVariable : stackFrame.visibleVariables()) {
            Value value = stackFrame.getValue(visibleVariable);
            if(value instanceof ObjectReference){
                ObjectReference objectReference = (ObjectReference) value;//is type java.util.HashMap
                Field entrySet = objectReference.referenceType().fieldByName("entrySet");// is java.util.HashMap.entrySet
                Value entrySetValue = objectReference.getValue(entrySet);// is null
                System.out.println(entrySet);

            }
        }
    }

在此处输入图像描述

for (T key : hashMap.keySet()) {
    V value = hashMap.get(key);
    // rest of your code here
} // Can you get to where you need to go from here?

Assuming hashMap is of type HashMap<T, V>.假设 hashMap 是 HashMap<T, V> 类型。

mapConfig.forEach((k, v) -> {

});

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