Question

有没有办法有效地增加实例名称，例如for-loop，就像这样？

for (int i=0; i<10; i++) {
    City city+i = new City();
}

该代码显然不起作用，但是我可以做些什么来创建名为City0，City1，City2等的10个对象？

Answer 1

您可以将城市添加到列表或数组中，然后按索引访问它们。 Java中列表方法的示例：

List<City> cities = new ArrayList<>();
for (int i = 0; i < 10; i++) {
    cities.add(new City());
}

然后，您可以像city.get(0)那样访问第一个city.get(1)第二个等等。

Answer 2

    <bill>
    <bill_detail>
    <detail type="T1" heading="PS"> 
      <section type="T1" heading="P1" sub_heading="A"> 
        <data_line type="T1"> 
          <text1>Employees</text1>  
          <text2>1</text2>  
          <text3>2</text3>  
      <text4>3</text4>  
      <text5>4</text5> 
    </data_line>  
    <total_line type="T1"> 
      <text1>Total</text1>  
      <text3>1</text3>  
      <text4>2</text4>  
      <text5>3</text5> 
    </total_line> 
  </section>  
  <section type="T1" sub_heading="B"> 
    <data_line type="T1"> 
      <text1>Single</text1>  
      <text2>1</text2>  
      <text3>2</text3>  
      <text4>3</text4>  
      <text5>4</text5> 
    </data_line>  
    <data_line type="T1"> 
      <text1>Family</text1>  
      <text2>1</text2>  
      <text3>2</text3>  
      <text4>3</text4>  
      <text5>4</text5> 
    </data_line>  
    <total_line type="T1"> 
      <text1>Total</text1>  
      <text3>1</text3>  
      <text4>2</text4>  
      <text5>3</text5> 
    </total_line> 
  </section>  
  <section type="T1" sub_heading="C"> 
    <data_line type="T1"> 
      <text1>Employees</text1>  
      <text2>1</text2>  
      <text3>2</text3>  
      <text4>3</text4>  
      <text5>4</text5> 
    </data_line>  
    <total_line type="T1"> 
      <text1>Total</text1>  
      <text3>1</text3>  
      <text4>2</text4>  
      <text5>3</text5> 
    </total_line> 
  </section>
  <section type="T1" heading="P2" sub_heading="A"> 
    <data_line type="T1"> 
      <text1>Employees</text1>  
      <text2>1</text2>  
      <text3>2</text3>  
      <text4>3</text4>  
      <text5>4</text5> 
    </data_line>  
    <total_line type="T1"> 
      <text1>Total</text1>  
      <text3>1</text3>  
      <text4>2</text4>  
      <text5>3</text5> 
    </total_line> 
  </section>  
  <section type="T1" sub_heading="B"> 
    <data_line type="T1"> 
      <text1>Single</text1>  
      <text2>1</text2>  
      <text3>2</text3>  
      <text4>3</text4>  
      <text5>4</text5> 
    </data_line>  
    <data_line type="T1"> 
      <text1>Family</text1>  
      <text2>1</text2>  
      <text3>2</text3>  
      <text4>3</text4>  
      <text5>4</text5> 
    </data_line>  
    <total_line type="T1"> 
      <text1>Total</text1>  
      <text3>1</text3>  
      <text4>2</text4>  
      <text5>3</text5> 
    </total_line> 
  </section>  
  <section type="T1" sub_heading="C"> 
    <data_line type="T1"> 
      <text1>Employees</text1>  
      <text2>1</text2>  
      <text3>2</text3>  
      <text4>3</text4>  
      <text5>4</text5> 
    </data_line>  
    <total_line type="T1"> 
      <text1>Total</text1>  
      <text3>1</text3>  
      <text4>2</text4>  
      <text5>3</text5> 
    </total_line> 
  </section>  
</detail>
</bill_detail>
</bill>

增加实例名称

2 个答案: