Java - 从文本文件创建字符串数组

时间:2012-10-12 10:38:50

标签: java string

我有一个这样的文本文件:

abc def jhi
klm nop qrs
tuv wxy zzz

我想要一个字符串数组,如:

String[] arr = {"abc def jhi","klm nop qrs","tuv wxy zzz"}

我试过了:

try
    {
        FileInputStream fstream_school = new FileInputStream("text1.txt");
        DataInputStream data_input = new DataInputStream(fstream_school);
        BufferedReader buffer = new BufferedReader(new InputStreamReader(data_input));
        String str_line;
        while ((str_line = buffer.readLine()) != null)
        {
            str_line = str_line.trim();
            if ((str_line.length()!=0)) 
            {
                String[] itemsSchool = str_line.split("\t");
            }
        }
    }
catch (Exception e)  
    {
     // Catch exception if any
        System.err.println("Error: " + e.getMessage());
    }

任何人都可以帮助我.... 所有答案都将不胜感激......

7 个答案:

答案 0 :(得分:10)

如果使用Java 7,由于the Files#readAllLines method

,可以在两行中完成
List<String> lines = Files.readAllLines(yourFile, charset);
String[] arr = lines.toArray(new String[lines.size()]);

答案 1 :(得分:2)

使用BufferedReader读取文件,使用readLine作为字符串读取每一行,并将它们放在ArrayList中,在循环结束时调用toArray。

答案 2 :(得分:1)

根据您的输入,您几乎就在那里。你错过了你的循环点,从文件中读取每一行。由于您没有先验知道文件中的总行数,因此使用集合(动态分配的大小)来获取所有内容,然后将其转换为String的数组(因为这是您想要的输出)。

这样的事情:

    String[] arr= null;
    List<String> itemsSchool = new ArrayList<String>();

    try 
    { 
        FileInputStream fstream_school = new FileInputStream("text1.txt"); 
        DataInputStream data_input = new DataInputStream(fstream_school); 
        BufferedReader buffer = new BufferedReader(new InputStreamReader(data_input)); 
        String str_line; 

        while ((str_line = buffer.readLine()) != null) 
        { 
            str_line = str_line.trim(); 
            if ((str_line.length()!=0))  
            { 
                itemsSchool.add(str_line);
            } 
        }

        arr = (String[])itemsSchool.toArray(new String[itemsSchool.size()]);
    }

然后输出(arr)将是:

{"abc def jhi","klm nop qrs","tuv wxy zzz"} 

这不是最佳解决方案。其他更多聪明的答案已经给出。这只是您当前方法的解决方案。

答案 3 :(得分:1)

这是我的代码,用于根据文本文件生成随机电子邮件以创建数组。

import java.io.*;

public class Generator {
    public static void main(String[]args){

        try {

            long start = System.currentTimeMillis();
            String[] firstNames = new String[4945];
            String[] lastNames = new String[88799];
            String[] emailProvider ={"google.com","yahoo.com","hotmail.com","onet.pl","outlook.com","aol.mail","proton.mail","icloud.com"};
            String firstName;
            String lastName;
            int counter0 = 0;
            int counter1 = 0;
            int generate = 1000000;//number of emails to generate

            BufferedReader firstReader = new BufferedReader(new FileReader("firstNames.txt"));
            BufferedReader lastReader = new BufferedReader(new FileReader("lastNames.txt"));
            PrintWriter write = new PrintWriter(new FileWriter("emails.txt", false));


            while ((firstName = firstReader.readLine()) != null) {
                firstName = firstName.toLowerCase();
                firstNames[counter0] = firstName;
                counter0++;
            }
            while((lastName= lastReader.readLine()) !=null){
                lastName = lastName.toLowerCase();
                lastNames[counter1]=lastName;
                counter1++;
            }

            for(int i=0;i<generate;i++) {
                write.println(firstNames[(int)(Math.random()*4945)]
                        +'.'+lastNames[(int)(Math.random()*88799)]+'@'+emailProvider[(int)(Math.random()*emailProvider.length)]);
            }
            write.close();
            long end = System.currentTimeMillis();

            long time = end-start;

            System.out.println("it took "+time+"ms to generate "+generate+" unique emails");

        }
        catch(IOException ex){
            System.out.println("Wrong input");
        }
    }
}

答案 4 :(得分:0)

您可以使用某些输入流或扫描仪逐行读取文件,然后将该行存储在String Array中。示例代码将为..

 File file = new File("data.txt");

        try {
            //
            // Create a new Scanner object which will read the data 
            // from the file passed in. To check if there are more 
            // line to read from it we check by calling the 
            // scanner.hasNextLine() method. We then read line one 
            // by one till all line is read.
            //
            Scanner scanner = new Scanner(file);
            while (scanner.hasNextLine()) {
                String line = scanner.nextLine();
                //store this line to string [] here
                System.out.println(line);
            }
        } catch (FileNotFoundException e) {
            e.printStackTrace();
        }

答案 5 :(得分:0)

    Scanner scanner = new Scanner(InputStream);//Get File Input stream here
    StringBuilder builder = new StringBuilder();
    while (scanner.hasNextLine()) {
        builder.append(scanner.nextLine());
        builder.append(" ");//Additional empty space needs to be added
    }
    String strings[] = builder.toString().split(" ");
    System.out.println(Arrays.toString(strings));

输出:

   [abc, def, jhi, klm, nop, qrs, tuv, wxy, zzz]

您可以阅读有关扫描仪here

的更多信息

答案 6 :(得分:0)

您可以使用readLine函数读取文件中的行并将其添加到数组中。

示例:

  File file = new File("abc.txt");
  FileInputStream fin = new FileInputStream(file);
  BufferedReader reader = new BufferedReader(fin);

  List<String> list = new ArrayList<String>();
  while((String str = reader.readLine())!=null){
     list.add(str);
  }

  //convert the list to String array
  String[] strArr = Arrays.toArray(list);

上面的数组包含您所需的输出。