java简单实现文件的创建 读写

import java.io.File;
import java.io.IOException;

/**
 * 创建文件
 * 
 * @author chendongj
 * 
 */
public class CreateFile {

	public void createFile(String path) {
		File aFile = new File(path);

		try {
			if (aFile.exists()) {
				aFile.delete();
				aFile.createNewFile();
				System.out.println("创建文件成功！");
			} else {
				aFile.createNewFile();
				System.out.println("创建文件成功！");
			}
		} catch (IOException e) {
			e.printStackTrace();
		}

	}

	public static void main(String[] args) {
		CreateFile cf = new CreateFile();
		cf.createFile("E:/test.txt");

	}

}

import java.io.File;
import java.io.FileWriter;
import java.io.IOException;

/**
 * 
 * @author 向文件写内容
 * 
 */
public class Write2File {
	public void write2File(String path) {

		try {
			File aFile = new File(path);
			FileWriter out = new FileWriter(aFile, true);
			out.write("11111111");
			out.flush();
			System.out.println("写入成功！");
			out.close();
		} catch (IOException e) {
			e.printStackTrace();
		}

	}

}

import java.io.File;
import java.io.FileNotFoundException;
import java.io.FileReader;
import java.io.IOException;

/**
 * 从文件中读内容
 * 
 * @author chendongj
 * 
 */
public class ReadFromFile {
	public void readFromFile(String path) {
		System.out.println("读取内容：");
		try {
			FileReader fr = new FileReader(new File(path));
			while (fr.read() != -1) {
				System.out.print((char) fr.read());

			}
			fr.close();
		} catch (FileNotFoundException e) {
			e.printStackTrace();
		} catch (IOException e) {
			e.printStackTrace();
		}

	}

}

public class TestFile {

	/**
	 * 测试文件创建 读写
	 */
	public static void main(String[] args) {
		String path = "E:/test.txt";
		CreateFile createFile = new CreateFile();
		createFile.createFile(path);

		Write2File w2f = new Write2File();
		w2f.write2File(path);

		ReadFromFile rff = new ReadFromFile();
		rff.readFromFile(path);

	}

}