Java –如何将字符串保存到文件

拼搏现实的明天。 2023-02-15 05:18 9阅读 0赞

在Java中，有很多方法可以将String写入文件。

## 1. Java 11 – Files.writeString ##

最后，在`java.nio`添加了一个新方法，可以轻松地将字符串保存到`File` 。

StringToFileJava11.java

package com.mkyong;
    
    import java.io.IOException;
    import java.nio.charset.StandardCharsets;
    import java.nio.file.Files;
    import java.nio.file.Paths;
    import java.nio.file.StandardOpenOption;
    
    public class StringToFileJava11 {
    
        public static void main(String[] args) {
    
            String content = "Hello World \r\nJava!\r\n";
            String path = "c:\\projects\\app.log";
    
            try {
    
                // Java 11 , default StandardCharsets.UTF_8
                Files.writeString(Paths.get(path), content);
    
                // encoding
                // Files.writeString(Paths.get(path), content, StandardCharsets.US_ASCII);
    
                // extra options
                // Files.writeString(Paths.get(path), content, 
    			//		StandardOpenOption.CREATE, StandardOpenOption.APPEND);
    
            } catch (IOException e) {
                e.printStackTrace();
            }
    
        }
    
    }

c:\\\\projects\\\\app.log

Hello World 
    Java!

## 2. Java 7 – Files.write ##

StringToFileJava7.java

package com.mkyong;
    
    import java.io.IOException;
    import java.nio.charset.StandardCharsets;
    import java.nio.file.Files;
    import java.nio.file.Paths;
    import java.nio.file.StandardOpenOption;
    
    public class StringToFileJava7 {
    
        public static void main(String[] args) {
    
            String content = "Hello World \r\nJava!\r\n";
            String path = "c:\\projects\\app.log";
    		
            try {
    
                // Java 7
                Files.write(Paths.get(path), content.getBytes());
    
                // encoding
                // Files.write(Paths.get(path), content.getBytes(StandardCharsets.UTF_8));
    
                // extra options
                // Files.write(Paths.get(path), content.getBytes(), 
    			//		StandardOpenOption.CREATE, StandardOpenOption.APPEND);
    
            } catch (IOException e) {
                e.printStackTrace();
            }
    
        }
    
    }

输出量

c:\\\\projects\\\\app.log

Hello World 
    Java!

## 3. Apache Commons IO ##

pom.xml

<dependency>
    		<groupId>commons-io</groupId>
    		<artifactId>commons-io</artifactId>
    		<version>2.6</version>
    	</dependency>

CommonsIOExample.java

package com.mkyong;
    
    import org.apache.commons.io.FileUtils;
    
    import java.io.File;
    import java.io.IOException;
    import java.nio.charset.StandardCharsets;
    
    public class CommonsIOExample {
    
        public static void main(String[] args) {
    
            String content = "Hello World \r\nJava!\r\n";
            String path = "c:\\projects\\app2.log";
    
            try {
                FileUtils.writeStringToFile(new File(path), content, StandardCharsets.UTF_8);
    
                // append
                // FileUtils.writeStringToFile(new File(path), content, StandardCharsets.UTF_8, true);
            } catch (IOException e) {
                e.printStackTrace();
            }
        }
    
    }

## 4. BufferedWriter ##

4.1在过去：

BufferedWriterExample.java

package com.mkyong;
    
    import java.io.BufferedWriter;
    import java.io.FileWriter;
    import java.io.IOException;
    
    public class BufferedWriterExample {
    
        public static void main(String[] args) {
    
            String content = "Hello World \r\nJava!\r\n";
            String path = "c:\\projects\\app.log";
    
            try (FileWriter writer = new FileWriter(path);
                  BufferedWriter bw = new BufferedWriter(writer)) {
    
                bw.write(content);
    
            } catch (IOException e) {
                e.printStackTrace();
            }
    
        }
    
    }

4.2或者像这样，手动关闭所有资源resources

BufferedWriterExampleBeforeJava7.java

package com.mkyong;
    
    import java.io.BufferedWriter;
    import java.io.FileWriter;
    import java.io.IOException;
    
    public class BufferedWriterExampleBeforeJava7 {
    
        public static void main(String[] args) {
    
            String content = "Hello World \r\nJava!\r\n";
            String path = "c:\\projects\\app.log";
    
            BufferedWriter bw = null;
            FileWriter fw = null;
    
            try {
    
                fw = new FileWriter(path);
                bw = new BufferedWriter(fw);
                
                bw.write(content);
    
            } catch (IOException e) {
                e.printStackTrace();
            } finally {
                try {
                    if (bw != null)
                        bw.close();
    
                    if (fw != null)
                        fw.close();
    
                } catch (IOException ex) {
                    ex.printStackTrace();
                }
            }
        }
    
    }

## 参考文献 ##

*  [文件Java文档][Java]
 *  [Java教程–读取，写入和创建文件][Java 1]
 *  [BufferedWriter JavaDocs][]
 *  [Java –如何将文本追加到文件][Java 2]
 *  [Java –如何创建和写入文件][Java 3]

标签： [文件][Link 1] [Java 11][] [Java 7][] [java.io][] [java.nio][] [写入文件][Link 2]

> 翻译自: [https://mkyong.com/java/java-how-to-save-a-string-to-a-file/][https_mkyong.com_java_java-how-to-save-a-string-to-a-file]

[Java]: https://docs.oracle.com/en/java/javase/11/docs/api/java.base/java/nio/file/Files.html
[Java 1]: https://docs.oracle.com/javase/tutorial/essential/io/file.html
[BufferedWriter JavaDocs]: https://docs.oracle.com/javase/8/docs/api/java/io/BufferedWriter.html
[Java 2]: https://www.mkyong.com/java/java-how-to-append-text-to-a-file/
[Java 3]: https://www.mkyong.com/java/java-how-to-create-and-write-to-a-file/
[Link 1]: https://mkyong.com/tag/file/
[Java 11]: https://mkyong.com/tag/java-11/
[Java 7]: https://mkyong.com/tag/java-7/
[java.io]: https://mkyong.com/tag/java-io/
[java.nio]: https://mkyong.com/tag/java-nio/
[Link 2]: https://mkyong.com/tag/write-file/
[https_mkyong.com_java_java-how-to-save-a-string-to-a-file]: https://mkyong.com/java/java-how-to-save-a-string-to-a-file/