打印格式化输出时出现列间距问题

Question

所以这是我需要格式化的代码片段：

double textbookprice = 0, tradebookprice = 0;
for(int i=0;i<tempTextbooks.size();i++) {
    System.out.println(tempTextbooks.get(i).dataMember +"\t "+tempTextbooks.get(i).title +"\t "+tempTextbooks.get(i).author+"\t $"+df.format(tempTextbooks.get(i).getPrice()));
    textbookprice = textbookprice + tempTextbooks.get(i).getPrice();
}

这就是我得到的输出，

COS221   Introduction to Programming with C++    Y. Daniel Liang     $120.99
COS225   Java Foundations    John Lewis  $94.59
BUS398   Excel 2010 Power Programming with VBA   John Walkenbach     $87.99

我需要班级编号/标题/作者/价格都有自己的专栏

Answer 1

您可以使用System.out.format来定义字段的长度。像这样的东西

System.out.format("%-10s %-40s %-20s %-15s \n", tempTextbooks.get(i).dataMember, tempTextbooks.get(i).title, tempTextbooks.get(i).author, df.format(tempTextbooks.get(i).getPrice()));

这会将前四列的宽度修复为10,40,20和15个字符。它们之前的-表示您希望它们保持对齐。 （如果您想要右对齐表，可以删除-。）

您可以根据自己的要求进行更改。

修改

我尝试使用此代码重现此问题

public class HelloWorld {
    public static void main(String[] args) {
        String[] s1 = {"COS221", "COS225", "BUS398"};
        String[] s2 = {"Introduction to Programming with C++", "Java Foundations", "Excel 2010 Power Programming with VBA"};
        String[] s3 = {"Y. Daniel Liang", "John Lewis", "John Walkenbach"};
        String[] s4 = {"$120.99", "$94.59", "$87.99"};

        for (int i = 0; i < 3; i++) {
            System.out.format("%-10s %-40s %-20s %-15s \n", s1[i], s2[i], s3[i], s4[i]);
        }
    }
}

输出如下：

COS221     Introduction to Programming with C++     Y. Daniel Liang      $120.99         
COS225     Java Foundations                         John Lewis           $94.59          
BUS398     Excel 2010 Power Programming with VBA    John Walkenbach      $87.99