扩展了两个方法，一个read()一个是appendText()，主要是appendText我觉得挺有用，新手手敲，大家给意见：）
[mw_shl_code=java,true]import java.io.FileOutputStream;
import java.io.IOException;
import java.io.InputStream;
import java.io.OutputStream;
public class FileExtend extends File {
private static final long serialVersionUID = -3641281297280978372L;
public FileExtend(String pathname) {
super(pathname);
}
/**
* 从文本文件中读取所有字符串
*
* @return 读取到的所有字符串
* @throws FileNotFoundException
*/
public String read() throws FileNotFoundException {
File file = new File(super.getPath());
if(!file.exists())throw new FileNotFoundException();
InputStream fis = null;
try {
fis = new FileInputStream(file);
int len = 0;
byte[] ch = new byte[(int) file.length()];
len = fis.read(ch);
return new String(ch, 0, len);
} catch (FileNotFoundException e) {
e.printStackTrace();
} catch (IOException e) {
e.printStackTrace();
} finally {
try {
if (fis != null) {
fis.close();
}
} catch (IOException e) {
e.printStackTrace();
}
}
return null;
}
/**
* 追加给定字符串到指定文本文件中
*
* @param appendStr
* 待追加的字符串
*/
public void appendText(String appendStr) {
if (appendStr == null)
throw new NullPointerException();
if (appendStr.trim().length() == 0)
throw new IllegalArgumentException("Append string too short");
OutputStream fos = null;
String path = super.getPath();// 获得父类的变量值
try {
if (new File(path).exists()) {
String srcContent = read();// 获得文本文件的原内容
fos = new FileOutputStream(path);
String str = srcContent + appendStr;// 拼接出新的内容
byte[] bt = str.getBytes();
fos.write(bt);// 写入新内容
}
} catch (FileNotFoundException e) {
e.printStackTrace();
} catch (IOException e) {
e.printStackTrace();
} finally {
if (fos != null) {
try {
fos.close();
} catch (IOException e) {
e.printStackTrace();
}
}
}
}
}
[/mw_shl_code]
本帖最后由 小野千帆 于 2012-8-24 14:29 编辑
好多try...catch......
我的话我会全部写在throws后面就不管了......
读取的话我一直用的thinking in java里的代码：
[mw_shl_code=java,true]public class BufferedInputFile {
public static String read(String filename) throws IOException{
BufferedReader in=new BufferedReader(new FileReader(filename));
String s;
StringBuilder sb=new StringBuilder();
while((s=in.readLine())!=null){
sb.append(s);
}
in.close();
return sb.toString();
}
}[/mw_shl_code]
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