Jav读写文件

最新推荐文章于 2024-07-24 12:30:59 发布

原创最新推荐文章于 2024-07-24 12:30:59 发布 · 1k 阅读

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本文详细介绍了使用Java进行文件读写操作的方法，包括如何创建文件对象、使用BufferedReader读取文件内容以及使用RandomAccessFile进行高效写入。通过实例演示了如何将字符串内容写入文件，并展示了文件读取和关闭操作的基本步骤。

package test2;

import java.io.BufferedReader;
import java.io.File;
import java.io.FileReader;
import java.io.IOException;
import java.io.RandomAccessFile;

public class CommonFile {

	private String m_fileName = "";
	private File m_File = null;
	private BufferedReader m_reader = null;

	public CommonFile(String strFileName) {
		m_fileName = strFileName;
		m_File = new File(m_fileName);
		try {
			m_reader = new BufferedReader(new FileReader(m_File));
		} catch (IOException e) {

		}		
	}

	public static boolean writeFile(String strFileName, String content) {

		try {

			RandomAccessFile randomFile = new RandomAccessFile(strFileName,"rw");
			long fileLength = randomFile.length();

			randomFile.seek(fileLength);
			randomFile.writeBytes(content);
			randomFile.close();
		} catch (IOException e) {
			return false;
		}

		return true;
	}

	public String ReadLine() {

		if (!m_File.exists()) {
			return null;
		}

		if (m_reader == null) {
			return null;
		}

		try {
			String tempString = m_reader.readLine();
			return tempString;
		} catch (IOException e) {

		}

		return "";
	}

	protected void close() {
		if (m_reader != null) {
			try {
				m_reader.close();
			} catch (IOException e) {
			}
		}
	}

	/**
	 * @param args
	 */
	public static void main(String[] args) {

		CommonFile file = new CommonFile("d:\\1.txt");
		String line = null;
		while ((line = file.ReadLine()) != null) {
			System.out.println(line);
		}

		file.close();

		CommonFile.writeFile("d:\\1231.txt", "adsfasdfasdfasdfasdf");
		CommonFile.writeFile("d:\\1231.txt", "111111111111111111111");
	}

}