Question

java 文件读写中哪个方法能够统计读取的文件中的字符个数？？？？

Answer 1

public static void tongji(String file)throws IOException{
Map< Character, Integer> map=new HashMap<Character, Integer>();
InputStreamReader in=new InputStreamReader(new FileInputStream(file));
int b;
int all=0;
while((b=in.read())!=-1){
char ch=(char)b;
if(b=='\n'||b=='\r'||b=='，'||b=='。'||b==' '){
continue;
}
Integer n=map.get(ch);
map.put(ch,n==null?1:n+1);
all++;
}

ArrayList<Entry<Character,Integer>> list=new ArrayList<Map.Entry<Character,Integer>>(map.entrySet());
Collections.sort(list,new Comparator<Entry<Character,Integer>>() {
@Override
public int compare(Entry<Character, Integer> o1,
Entry<Character, Integer> o2) {
return o2.getValue()-o1.getValue();
}
});
System.out.println("总字数"+all);
System.out.println("出现的字符数："+list.size());
for(Entry entry:list){
char ch=(Character) entry.getKey();
int c=(Integer) entry.getValue();

System.out.println(ch+"="+c);
}

}

Answer 2

File file=new File("c:\\abc.txt");
System.out.print(file.length());

Answer 3

用你创建的File对象的size()方法试试！希望及时采纳！