读取文本内容，从高到低排序，并将排序结果写入另一个文件

假如d:/a.txt文件中有以下内容： 01,咖啡,20.5,10 02,伴侣,30.8,2 03,咖啡杯,28,5 04,勺子,5.5,5 需求： 1、写程序读取文件中的数据 2、然后将商品信息按照价格由高到低排序 3、将排序结果输出到一个文件中:d:/price_order.txt 写出源代码、运行调试的过程和结果。

主要用到Java IO六输入输出啊，先做第一步，接收输入文件内容：

<span class="hljs-keyword">package</span> com.test.server;

<span class="hljs-keyword">import</span> java.io.FileNotFoundException;
<span class="hljs-keyword">import</span> java.io.FileReader;
<span class="hljs-keyword">import</span> java.io.IOException;
<span class="hljs-keyword">import</span> java.io.Reader;


<span class="hljs-keyword">public</span> <span class="hljs-keyword">class</span> <span class="hljs-title class_">Test2</span> {
    <span class="hljs-keyword">public</span> <span class="hljs-keyword">static</span> <span class="hljs-keyword">void</span> <span class="hljs-title function_">main</span><span class="hljs-params">(String[] args)</span> {
        <span class="hljs-type">Reader</span> <span class="hljs-variable">fr</span> <span class="hljs-operator">=</span> <span class="hljs-literal">null</span>;
        <span class="hljs-type">int</span> <span class="hljs-variable">length</span> <span class="hljs-operator">=</span> <span class="hljs-number">0</span>;
        <span class="hljs-type">char</span> ch [] = <span class="hljs-literal">null</span>;
        <span class="hljs-comment">//创建字符输入流对象，负责读取文件</span>
        <span class="hljs-keyword">try</span> {
            fr =<span class="hljs-keyword">new</span> <span class="hljs-title class_">FileReader</span>(<span class="hljs-string">"C:\\text.txt"</span>);
            <span class="hljs-comment">//创建中转站数组，存放读取的内容</span>
            ch = <span class="hljs-keyword">new</span> <span class="hljs-title class_">char</span>[<span class="hljs-number">1024</span>];
            <span class="hljs-comment">//读取文件内容到ch数组中</span>
            length = fr.read(ch);
            <span class="hljs-comment">//输出保存在ch数组中文件内容</span>
            System.out.println(<span class="hljs-keyword">new</span> <span class="hljs-title class_">String</span>(ch ,<span class="hljs-number">0</span>,length));
            
        } <span class="hljs-keyword">catch</span> (FileNotFoundException e) {
            <span class="hljs-comment">// TODO Auto-generated catch block</span>
            e.printStackTrace();
        } <span class="hljs-keyword">catch</span> (IOException e) {
            <span class="hljs-comment">// TODO Auto-generated catch block</span>
            e.printStackTrace();
        }<span class="hljs-keyword">finally</span>{
            <span class="hljs-keyword">if</span>(<span class="hljs-literal">null</span>!=fr){
                <span class="hljs-keyword">try</span> {
                    fr.close();
                } <span class="hljs-keyword">catch</span> (IOException e) {
                    <span class="hljs-comment">// TODO Auto-generated catch block</span>
                    e.printStackTrace();
                }
            }
        }
    }
}