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我在网上MOOC学习有关构造函数创建时的构造，我有如下的原始代码片段：错误Java的最后一个变量声明为其他变量
package com.example.accountapp.logic;
import com.example.accountapp.ui.OutputInterface;
/**
* This file defines the Account class. It provides the basis for a
* series of improvements you'll need to make as you progress through
* the lessons in Module 6.
*/
public class Account {
/**
* This is the variable that stores our OutputInterface instance.
* <p/>
* This is how we will interact with the User Interface
* [MainActivity.java].
* </p>
* This was renamed to 'mOut' from 'out', as it is in the video
* lessons, to better match Android/Java naming guidelines.
*/
final OutputInterface mOut;
/**
* Name of the account holder.
*/
String name;
/**
* Number of the account.
*/
int number;
/**
* Current balance in the account.
*/
double balance;
/**
* Constructor initializes the field
*/
public Account(OutputInterface out) {
mOut = out;
}
/**
* Deposit @a amount into the account.
*/
public void deposit(double amount) {
balance += amount;
}
/**
* Withdraw @a amount from the account. Prints "Insufficient
* Funds" if there's not enough money in the account.
*/
public void withdrawal(double amount) {
if (balance > amount)
balance -= amount;
else
mOut.println("Insufficient Funds");
}
/**
* Display the current @a amount in the account.
*/
public void displayBalance() {
mOut.println("The balance on account "
+ number
+ " is "
+ balance);
}
}
现在我需要将所有变量更改为私有，并为字段名称，数字和余额添加构造函数。
我创建如下两个构造函数：
public Account(double newBalance){balance = newBalance;}
public Account(String newName, int newNumber, double newBalance){
this(newBalance);
name = newName;
number = newNumber;
}
添加这些构造导致错误的如下最终变量声明：
MOUT的变量可能尚未初始化。
当我删除我的两个新的构造函数或从变量mOut中删除final时，错误消失。
我可以知道为什么这个错误发生？我试着通过StackOverflow寻找答案，但无法找到类似的情况。谢谢。
这是因为不是所有的构造函数将初始化'mOut'。 – Li357
如果有人调用其中一个新的构造函数，则不会设置“mOut”。有什么不清楚的情况？ –
我不知道为什么它不是那么与其他变量（所有变量必须在每个构造函数声明），但只有与类型决赛。 – yogescicak