java读取文件的几种方法！！
public?class?AppendToFile?{
????/**
?????*?A方法追加文件：使用RandomAccessFile
?????*/
????public?static?void?appendMethodA(String?fileName,?String?content)?{
????????try?{
????????????//?打开一个随机访问文件流，按读写方式
????????????RandomAccessFile?randomFile?=?new?RandomAccessFile(fileName,?"rw");
????????????//?文件长度，字节数
????????????long?fileLength?=?randomFile.length();
????????????//将写文件指针移到文件尾。
????????????randomFile.seek(fileLength);
????????????randomFile.writeBytes(content);
????????????randomFile.close();
????????}?catch?(IOException?e)?{
????????????e.printStackTrace();
????????}
????}
????/**
?????*?B方法追加文件：使用FileWriter
?????*/
????public?static?void?appendMethodB(String?fileName,?String?content)?{
????????try?{
????????????//打开一个写文件器，构造函数中的第二个参数true表示以追加形式写文件
????????????FileWriter?writer?=?new?FileWriter(fileName,?true);
????????????writer.write(content);
????????????writer.close();
????????}?catch?(IOException?e)?{
????????????e.printStackTrace();
????????}
????}
????public?static?void?main(String[]?args)?{
????????String?fileName?=?"C:/temp/newTemp.txt";
????????String?content?=?"new?append!";
????????//按方法A追加文件
????????AppendToFile.appendMethodA(fileName,?content);
????????AppendToFile.appendMethodA(fileName,?"append?end.?\n");
????????//显示文件内容
????????ReadFromFile.readFileByLines(fileName);
????????//按方法B追加文件
????????AppendToFile.appendMethodB(fileName,?content);
????????AppendToFile.appendMethodB(fileName,?"append?end.?\n");
????????//显示文件内容
????????ReadFromFile.readFileByLines(fileName);
????}
}
