转自：http://blog.csdn.net/wgw335363240/article/details/5678965
下边列举出了三种向文件中写入数据的方式，当然还有其他方式，帮助自己理解文件写入类的继承关系，分享出来供初学者使用。类的关系：
file->fileoutputstream->outputstreamWriter(FileWriter继承outputstreamWriter对象)
注意：可以参照jdk-API，见http://tool.oschina.net/apidocs/apidoc?api=jdk-zh的java.io包下面的文件读写方法
测试代码：
package com.test.csdn;
import java.io.File;
import java.io.FileOutputStream;
import java.io.FileWriter;
import java.io.IOException;
import java.io.OutputStreamWriter;
/**
* 测试向文件中写文件
*
*/
public class TestWirteFile {
/**
* @param args
* @throws IOException
*/
public static void main(String[] args) throws IOException {
String sContent = "市场调研，2013年，美国平板电脑销售总量将超越台式机";
String sDestFile = "/home/rey/temp/myWrite.txt";
File destFile = new File(sDestFile);
if (!destFile.exists()) {
destFile.createNewFile();
}
// 1.向文件写入内容
// writeByFileWrite(sDestFile, sContent);
// 2.FileOutputStream向文件写入内容
// writeByFileWrite(sDestFile, sContent);
// 2.OutputStreamWriter向文件写入内容
writeByOutputStreamWrite(sDestFile, sContent);
}
/**
* 用FileWrite向文件写入内容
*
* @param _destFile
* @throws IOException
*/
public static void writeByFileWrite(String _sDestFile, String _sContent)throws IOException {
FileWriter fw = null;
try {
fw = new FileWriter(_sDestFile);
fw.write(_sContent);
} catch (Exception ex) {
ex.printStackTrace();
} finally {
if (fw != null) {
fw.close();
fw = null;
}
}
}
/**
* 用FileOutputStream向文件写入内容
*
* @param _destFile
* @throws IOException
*/
public static void writeByFileOutputStream(String _sDestFile, String _sContent) throws IOException {
FileOutputStream fos = null;
try {
fos = new FileOutputStream(_sDestFile);
fos.write(_sContent.getBytes());
} catch (Exception ex) {
ex.printStackTrace();
} finally {
if (fos != null) {
fos.close();
fos = null;
}
}
}
/**
* 用OutputStreamWrite向文件写入内容
*
* @param _destFile
* @throws IOException
*/
public static void writeByOutputStreamWrite(String _sDestFile, String _sContent) throws IOException {
OutputStreamWriter os = null;
FileOutputStream fos = null;
try {
fos = new FileOutputStream(_sDestFile);
os = new OutputStreamWriter(fos, "UTF-8");
os.write(_sContent);
} catch (Exception ex) {
ex.printStackTrace();
} finally {
if (os != null) {
os.close();
os = null;
}
if (fos != null) {
fos.close();
fos = null;
}
}
}
}//end class