在包含 html 代码的 .txt 文件中查找最大数字

Question

代码应该读取一个包含html代码的.txt文件，然后在提供的代码之间找到数字并打印出三段代码中最大的数字。大数应该是 42.25。提前致谢。

// 1.) <span class="green">24.52&nbsp;▲&nbsp;0.96%</span></td>
// 2.) <span class="green">0.68&nbsp;▲&nbsp;0.41%</span></td>
// 3.) <span class="green">42.25&nbsp;▲&nbsp;0.36%</span></td>

    // need to print out 42.25 as the largest number of the three above

public class LargestNumber {

    public static void name() {

        // this is the pattern before the name
        String patternBeforeName = "<td><a href=\"http://www.nasdaq.com/aspx/infoquotes.aspx?symbol=";

        // this is the pattern after the name
        String patternAfterName = "&amp;selected=";
        String bigText = IOMaster.readTextFile("Project1.txt");
        String patternBeforeValuePosative = "<td><span class=\"green\">";

        int indexOfBeginning = bigText.indexOf(patternBeforeValuePosative);

        while (indexOfBeginning >= 0) { // check if found)

            int indexOfEnd = bigText.indexOf(patternAfterName, indexOfBeginning); // start looking from the indexOfBeginning
            if (indexOfEnd >= 0) { // check if found
                String index = bigText.substring(indexOfBeginning + patternBeforeName.length(), indexOfEnd);

                // splits the text between the html tags </a></d>
                String[] indexList = index.split("</a></td>");

                // for statement
                for (int i = 0; i < indexList.length; i++) {
                    index = indexList[i];

                    // currently prints out 24.52
                    System.out.println("The name is:\t\t" + index);
                }
            }
            bigText = bigText.substring(indexOfEnd);
            indexOfBeginning = bigText.indexOf(patternBeforeName);
        }
    }
}

Answer 1

您可以使用正则表达式提取文本中的所有数字。之后你需要做的就是找到最大值。

public static List<Double> findNumbers(String bigText) {
    List<Double> numbers = new ArrayList<Double>();
    Pattern p = Pattern.compile("[0-9]+.[0-9]*|[0-9]*.[0-9]+|[0-9]+");
    Matcher m = p.matcher(bigText);
    while (m.find()) {
        numbers.add(Double.parseDouble(m.group());
    }
    return numbers;
}

然后你可以很容易地找到最大值：

public double findMaximum(List<Double> numbers) {
    double max = 0.0;
    for(double d: numbers) {
        if(d > max) max = d;
    }
    return max;
}