为了记录Puzzle 17的笔记, 需要写一个程序, 完成如下功能:
以下为该类的全文：
package hello;
import java.io.BufferedReader;
import java.io.File;
import java.io.FileNotFoundException;
import java.io.FileReader;
import java.io.FileWriter;
import java.io.IOException;
import java.io.PrintWriter;
import java.util.logging.Level;
import java.util.logging.Logger;
/**
* 完成字符串到Unicode转义字符的转化s
* @author iridium
*/
public class UnicodeConvertor {
public static void main(String[] args) {
UnicodeConvertor uc = new UnicodeConvertor();
uc.convertToUnicode(new File("/home/iridium/Documents/He.java"));
}
public static String strToUnicode(String str, int width) {
StringBuffer sb = new StringBuffer();
char[] array = str.toCharArray();
int count = 0;
for (char c : array) {
String s = Integer.toHexString(c);
if (s.length() < 4) {
s = "0000".substring(s.length()) + s;
}
sb.append("\\u").append(s);
count++;
if (count % width == 0) {
sb.append("\n");
count = 0;
}
}
return sb.toString();
}
public static String strToUnicode(String str) {
return strToUnicode(str, 10);
}
public static String fileToString(File file) {
FileReader fr = null;
StringBuffer sb = new StringBuffer();
try {
fr = new FileReader(file);
BufferedReader br = new BufferedReader(fr);
String s = br.readLine();
while (s != null) {
sb.append(s);
s = br.readLine();
}
return sb.toString();
} catch (FileNotFoundException ex) {
Logger.getLogger(UnicodeConvertor.class.getName()).log(Level.SEVERE, null, ex);
} catch (IOException ex) {
Logger.getLogger(UnicodeConvertor.class.getName()).log(Level.SEVERE, null, ex);
} finally {
try {
fr.close();
} catch (IOException ex) {
Logger.getLogger(UnicodeConvertor.class.getName()).log(Level.SEVERE, null, ex);
}
}
return null;
}
/**
* invoke converToUnicode(File, boolean), as the second parameter is true default
* @param file
*/
public void convertToUnicode(File file) {
this.convertToUnicode(file, true);
}
/**
* convert content of a file to Unicode escapes
* @param file source file to be converted
* @param bak if it equals true, a backup file will be kept
*/
public void convertToUnicode(File file, boolean bak) {
try {
String name = file.getCanonicalPath();
String nameBak = name + ".bak";
file.renameTo(new File(nameBak));
File distFile = new File(name);
String orginalSrc = this.fileToString(new File(nameBak));
String unicodeStr = this.strToUnicode(orginalSrc, 1000);
FileWriter fw = new FileWriter(distFile);
PrintWriter pw = new PrintWriter(fw);
pw.write(unicodeStr);
pw.close();
if (!bak) {
file.delete();
}
} catch (IOException ex) {
Logger.getLogger(UnicodeConvertor.class.getName()).log(Level.SEVERE, null, ex);
}
}
}
有很大的优化空间。
已知的问题：
附