如何从文件内容创建Java字符串？

我已经用下面这个成语有一段时间了。这似乎是传播最广的，至少在我访问过的网站上。

在Java中有没有更好/不同的方法将文件读入字符串？

private String readFile(String file) throws IOException {
    BufferedReader reader = new BufferedReader(new FileReader (file));
    String         line = null;
    StringBuilder  stringBuilder = new StringBuilder();
    String         ls = System.getProperty("line.separator");

    try {
        while((line = reader.readLine()) != null) {
            stringBuilder.append(line);
            stringBuilder.append(ls);
        }

        return stringBuilder.toString();
    } finally {
        reader.close();
    }
}

当前回答

如果您正在寻找不涉及第三方库（例如Commons I/O）的替代方案，可以使用Scanner类：

private String readFile(String pathname) throws IOException {

    File file = new File(pathname);
    StringBuilder fileContents = new StringBuilder((int)file.length());        

    try (Scanner scanner = new Scanner(file)) {
        while(scanner.hasNextLine()) {
            fileContents.append(scanner.nextLine() + System.lineSeparator());
        }
        return fileContents.toString();
    }
}

2008-11-28 19:00:35

其他回答

import java.nio.charset.StandardCharsets;
import java.nio.file.Files;
import java.nio.file.Paths;

Java 7

String content = new String(Files.readAllBytes(Paths.get("readMe.txt")), StandardCharsets.UTF_8);

Java 11

String content = Files.readString(Paths.get("readMe.txt"));

2016-10-28 07:04:17

public static String slurp (final File file)
throws IOException {
    StringBuilder result = new StringBuilder();

    BufferedReader reader = new BufferedReader(new FileReader(file));

    try {
        char[] buf = new char[1024];

        int r = 0;

        while ((r = reader.read(buf)) != -1) {
            result.append(buf, 0, r);
        }
    }
    finally {
        reader.close();
    }

    return result.toString();
}

2010-02-08 19:51:12

如果是文本文件，为什么不使用apachecommons io？

它有以下方法

public static String readFileToString(File file) throws IOException

如果要将行作为列表，请使用

public static List<String> readLines(File file) throws IOException

2011-10-17 15:34:03

使用代码：

File file = new File("input.txt");
BufferedInputStream bin = new BufferedInputStream(new FileInputStream(
                file));
byte[] buffer = new byte[(int) file.length()];
bin.read(buffer);
String fileStr = new String(buffer);

fileStr包含字符串形式的输出。

2017-01-16 06:53:39

import java.nio.file.Files;

.......

 String readFile(String filename) {
            File f = new File(filename);
            try {
                byte[] bytes = Files.readAllBytes(f.toPath());
                return new String(bytes,"UTF-8");
            } catch (FileNotFoundException e) {
                e.printStackTrace();
            } catch (IOException e) {
                e.printStackTrace();
            }
            return "";
    }

2012-04-16 14:33:59

如何从文件内容创建Java字符串？

推荐文章

最新文章

标签