用java编写程序 1.建立一个文本文件，输入英语短文.编写一个程序，统计该文件中英文字母的个数， java创建一个文本文件
\u7528java\u7f16\u5199\u4e00\u4e2a\u7a0b\u5e8f\uff0c\u5206\u522b\u7edf\u8ba1\u5e76\u8f93\u51fa\u6587\u672c\u6587\u4ef6\u4e2d\u5143\u97f3\u5b57\u6bcda,e,i,o,u\u7684\u4e2a\u6570public static void main(String[] args) throws Exception {
File f = new File("C:\\Users\\\u53f2\u6587\u5929\\Desktop\\\u65b0\u5efa\u6587\u672c\u6587\u68631.txt");
InputStream in = new FileInputStream(f);
InputStreamReader reader = new InputStreamReader(in);
// \u8fd9\u53e5\u8bdd\u4e0d\u8981\u5ffd\u7565\uff0c\u5b83\u5bf9\u4f60\u4ee5\u540e\u7f16\u5199\u9ad8\u6027\u80fdIO\u6d41\u6709\u81f3\u5173\u91cd\u8981\u7684\u7406\u89e3\uff0c\u6211\u5efa\u8bae\u4f60\u5148\u4e86\u89e3\u4e00\u4e0b\u7f13\u51b2\u533a\u7684\u6982\u5ff5
BufferedReader buffered = new BufferedReader(reader);
String text = "";
for (String line = buffered.readLine(); null != line; line = buffered.readLine()) {
text += line;
}
buffered.close();
int aTotal = 0;
int eTotal = 0;
int iTotal = 0;
int oTotal = 0;
int uTotal = 0;
for (int index = 0; index < text.length(); index++) {
if ('a' == text.charAt(index))
aTotal++;
if ('e' == text.charAt(index))
eTotal++;
if ('i' == text.charAt(index))
iTotal++;
if ('o' == text.charAt(index))
oTotal++;
if ('u' == text.charAt(index))
uTotal++;
}
System.out.println("a\u7684\u4e2a\u6570\u662f\uff1a" + aTotal);
System.out.println("e\u7684\u4e2a\u6570\u662f\uff1a" + eTotal);
System.out.println("i\u7684\u4e2a\u6570\u662f\uff1a" + iTotal);
System.out.println("o\u7684\u4e2a\u6570\u662f\uff1a" + oTotal);
System.out.println("u\u7684\u4e2a\u6570\u662f\uff1a" + uTotal);
}
\u53ef\u4ee5\u901a\u8fc7\u201cFileOutputStream\u201d\u521b\u5efa\u6587\u4ef6\u6587\u672c\u6587\u4ef6\uff0c\u4e4b\u540e\u8fc7\u201cOutputStreamWriter\u201d\u6d41\u7684\u5f62\u5f0f\u8fdb\u884c\u6587\u4ef6\u5185\u5bb9\u5b58\u50a8\uff0c\u4e3e\u4f8b\uff1a
OutputStreamWriter pw = null;//\u5b9a\u4e49\u4e00\u4e2a\u6d41
pw = new OutputStreamWriter(new FileOutputStream(\u201cD:/test.txt\u201d),"GBK");//\u786e\u8ba4\u6d41\u7684\u8f93\u51fa\u6587\u4ef6\u548c\u7f16\u7801\u683c\u5f0f\uff0c\u6b64\u8fc7\u7a0b\u521b\u5efa\u4e86\u201ctest.txt\u201d\u5b9e\u4f8b
pw.write("\u6211\u662f\u8981\u5199\u5165\u5230\u8bb0\u4e8b\u672c\u6587\u4ef6\u7684\u5185\u5bb9");//\u5c06\u8981\u5199\u5165\u6587\u4ef6\u7684\u5185\u5bb9\uff0c\u53ef\u4ee5\u591a\u6b21write
pw.close();//\u5173\u95ed\u6d41
\u5907\u6ce8\uff1a\u6587\u4ef6\u6d41\u7528\u5b8c\u4e4b\u540e\u5fc5\u987b\u53ca\u65f6\u901a\u8fc7close\u65b9\u6cd5\u5173\u95ed\uff0c\u5426\u5219\u4f1a\u4e00\u76f4\u5904\u4e8e\u6253\u5f00\u72b6\u6001\uff0c\u76f4\u81f3\u7a0b\u5e8f\u505c\u6b62\uff0c\u589e\u52a0\u7cfb\u7edf\u8d1f\u62c5\u3002
public class Read {
public static void main(String[] args) throws Exception {
long size = readFileByChars("D://test.txt");
write("D://test1.txt",size);
}
public static long readFileByChars(String fileName) {
File file = new File(fileName);
Reader reader = null;
int num =0;
try {
reader = new InputStreamReader(new FileInputStream(file));
int tempchar;
while ((tempchar = reader.read()) != -1) {
// 对于windows下，rn这两个字符在一起时，表示一个换行。
// 但如果这两个字符分开显示时，会换两次行。
// 因此，屏蔽掉r，或者屏蔽n。否则，将会多出很多空行。
if (((char) tempchar) != 'r') {
System.out.print((char) tempchar);
}
if (tempchar>= 'A' && tempchar<= 'Z' ||tempchar>= 'a' && tempchar<= 'z'){
num++;
}
}
reader.close();
} catch (Exception e) {
e.printStackTrace();
} finally {
if (reader != null) {
try {
reader.close();
} catch (IOException e1) {
}
}
}
return num;
}
public static void write(String fileName,long size) throws IOException {
File file = new File(fileName);
Writer writer = null;
try {
writer =new FileWriter(new File(fileName));
writer.write("英文字母共有:"+size);
}catch (Exception e){
e.printStackTrace();
}finally {
if (writer!= null){
writer.close();
}
}
}
}
第二题：
public class Read {
public static void main(String[] args) throws Exception {
readFile("D://test.txt");
}
public static void readFile(String fileName ) throws Exception {
BufferedReader isr = new BufferedReader(new FileReader(fileName));
String str = null;
int allnumber =1;
str = isr.readLine();
String [] strings = str.split("\\s+");
float [] sum ={Float.valueOf(strings[0]),Float.valueOf(strings[1]),Float.valueOf(strings[2])};
float [] min ={Float.valueOf(strings[0]),Float.valueOf(strings[1]),Float.valueOf(strings[2])};
float [] max ={Float.valueOf(strings[0]),Float.valueOf(strings[1]),Float.valueOf(strings[2])};
System.out.println(str);
while ((str = isr.readLine())!= null){
System.out.println(str);
deal(str,sum,min,max);
allnumber++;
}
if (isr!= null){
isr.close();
}
System.out.println("三门课最大值："+max[0]+""+max[1]+""+max[2]);
System.out.println("三门课最小值："+min[0]+""+min[1]+""+min[2]);
System.out.println("三门课平均值："+sum[0]/allnumber+""+sum[1]/allnumber+""+sum[2]/allnumber);
}
public static void deal(String str, float[] sum, float[] min, float[] max){
String [] strings = str.split("\\s+");
for (int i=0;i<3;i++) {
sum[i] = sum[i] + Float.valueOf(strings[i]);
if (max[i] < Float.valueOf(strings[i])) {
max[i] = Float.valueOf(strings[i]);
}
if (min[i] > Float.valueOf(strings[i])) {
min[i] = Float.valueOf(strings[i]);
}
}
}
}
package mainpackage;
/**
* 首先 得知道文件位置
* 然后 绑定文件的字符流
* 接着 得到字符流之后就可以每行进行字符读取
* 最后 得到每行字符后就可以判断了
* 注：我也是闲着没事，顺便写的。其实倒还写的有些复杂了
* 你有什么不懂得可以随时问我
* 在不在就不敢保证了
*
*/
import java.io.BufferedReader;
import java.io.File;
import java.io.FileReader;
import java.io.IOException;
public class ReadFileBytes {
public static void main(String[] args) throws IOException {
String fileDir = "H:/read.txt"; //文件路劲
File file = new File(fileDir); //实例化文件
FileReader in = new FileReader (file); //实例化文件读取对象
BufferedReader bf = new BufferedReader(in); //绑定字符流
String str ; //拼接字符对象
String deStr = ""; //拼接结果
int len = 0; //字母个数
while ((str = bf.readLine() )!=null) { //循环行，获取每行的字符并且进行拼接
deStr+=str;
}
byte[] b = deStr.getBytes(); //将拼接的字符串beye化
for(byte s:b){ //循环数据 如果为字母 就将长度加一
if(s>='A'&&s<='Z'||s>='a'&&s<='z'){
len++;
}
}
System.out.println(len); //打印长度
}
}
tretches before us in the constant panorama
扩展阅读：java编程零基础入门 ... java编程常用软件 ... 为什么都不建议java转测试 ... java简单入门程序代码 ... java代码生成器 ... java编程代码大全免费 ... 初学编程必背50个 ... java编程怎么建立类 包 ... 编写一个简单的java程序 ...
