第3章 课后作业

第3题,复制文本并读取

import java.io.BufferedReader;
import java.io.BufferedWriter;
import java.io.File;
import java.io.FileReader;
import java.io.FileWriter;


public class test {
public static void main(String[] args) {
File file = new File("C:\\source.txt");
File file1 = new File("D:\\target.txt");
FileWriter writer = null;
FileReader reader = null;
BufferedWriter bw = null;
BufferedReader br = null;
String str;
StringBuffer sb = new StringBuffer();
try {
reader = new FileReader(file);
br = new BufferedReader(reader);
writer = new FileWriter(file1);
bw = new BufferedWriter(writer);
while ((str = br.readLine()) != null) {
bw.write(str);
bw.newLine();
sb.append(str);
}
System.out.println("原文件内容为:" + sb);
System.out.println("原文件大小:" + file.length() + "字节");
} catch (Exception e) {
e.printStackTrace();
} finally {
try {
bw.close();
writer.close();
br.close();
reader.close();
} catch (Exception e) {
e.printStackTrace();
}
}
FileReader reader1 = null;
BufferedReader br1 = null;
String str1;
StringBuffer sb1 = null;
try {
reader1 = new FileReader(file1);
br1 = new BufferedReader(reader1);
sb1 = new StringBuffer();
while ((str1 = br1.readLine()) != null) {
sb1.append(str1);
}
System.out.println("新文件内容为:" + sb1);
System.out.println("新文件大小:" + file1.length() + "字节");
} catch (Exception e) {
e.printStackTrace();
} finally {
try {
br1.close();
reader1.close();
} catch (Exception e) {
e.printStackTrace();
}
}
}

}

第4题   编写程序读取Windows目录下的win.ini文件,并输出其内容

import java.io.BufferedReader;
import java.io.File;
import java.io.FileReader;


public class test1 {
public static void main(String[] args) {
File file = new File("C:\\Windows\\win.ini");
BufferedReader br = null;
try {
br = new BufferedReader(new FileReader(file));
String str;
StringBuffer sb = new StringBuffer();
while ((str = br.readLine()) != null) {
sb.append(str);
}
System.out.println(sb);
} catch (Exception e) {
e.printStackTrace();
} finally {
try {
br.close();
} catch (Exception e) {
e.printStackTrace();
}
}
}
}