如何从datasnapshot中检索所有数据？

DatabaseReference databaseRef = FirebaseDatabase.getInstance().getReference("your_node");
databaseRef.addListenerForSingleValueEvent(new ValueEventListener() {
    @Override
    public void onDataChange(DataSnapshot dataSnapshot) {
        Iterable<DataSnapshot> children = dataSnapshot.getChildren();
        for (DataSnapshot child : children) {
            Object value = child.getValue();
            // 处理当前子节点的值
            System.out.println(value.toString());
            
            // 如果需要进一步处理子节点的子节点
            DataSnapshot grandChild = child.child("grand_child_node");
            Object grandChildValue = grandChild.getValue();
            // 处理子节点的子节点的值
            System.out.println(grandChildValue.toString());
        }
    }

    @Override
    public void onCancelled(DatabaseError databaseError) {
        // 处理取消事件
    }
});