readInput加上文件是否读完的判断f.getFilePointer() < f.length() public static void readInput() { try { RandomAccessFile f = new RandomAccessFile("test.txt", "rw"); int i; double[] b; double a = 0, sum = 0; b = new double[5]; // double d; f.seek(0); for (i = 0; i < 5 && f.getFilePointer() < f.length(); i++) { b[i] = f.readDouble(); // d=f.readDouble()-'0'; System.out.println("[" + i + "]:" + b[i]);// 这里之后就运行不了了 } System.out.println("aaaa:"); for (i = 0; i < 5; i++) { System.out.println("[" + i + "]:" + b[i]); sum += b[i]; } a = sum / 5; f.seek(16); f.writeDouble(a); f.close(); } catch (IOException e) { System.err.println("发生异常:" + e); e.printStackTrace(); } }
package aa;import java.io.File; import java.io.FileReader; import java.io.FileWriter; import java.io.IOException; import java.io.InputStreamReader; import java.util.ArrayList; import java.util.List;public class Test11 { public static void writemethod(File file, InputStreamReader ips) throws IOException { FileWriter fw = new FileWriter(file); if (!file.exists()) { file.createNewFile(); } int i; while ((i = ips.read()) != 13) { fw.write((char) i); } fw.close(); ips.close(); } public static int readmethod(File file) throws IOException { FileReader fr = new FileReader(file); int i; List<String> list = new ArrayList<String>(); while ((i = fr.read()) != -1) { String val = ""; while (i != 32&i != -1) { val = val + (char) i; i = fr.read(); } list.add(val); } int sum = 0; for (String v : list) { int kk = Integer.parseInt(v); sum = sum + kk; } return sum / list.size(); } public static void main(String[] args) throws IOException { InputStreamReader ips = new InputStreamReader(System.in); File file = new File("f://test3.txt"); writemethod(file, ips); System.out.println(readmethod(file)); } }
public static void readInput() {
try {
RandomAccessFile f = new RandomAccessFile("test.txt", "rw");
int i;
double[] b;
double a = 0, sum = 0;
b = new double[5];
// double d;
f.seek(0);
for (i = 0; i < 5 && f.getFilePointer() < f.length(); i++) {
b[i] = f.readDouble();
// d=f.readDouble()-'0';
System.out.println("[" + i + "]:" + b[i]);// 这里之后就运行不了了 }
System.out.println("aaaa:");
for (i = 0; i < 5; i++) {
System.out.println("[" + i + "]:" + b[i]);
sum += b[i];
}
a = sum / 5; f.seek(16);
f.writeDouble(a); f.close();
} catch (IOException e) {
System.err.println("发生异常:" + e);
e.printStackTrace();
}
}
import java.io.FileReader;
import java.io.FileWriter;
import java.io.IOException;
import java.io.InputStreamReader;
import java.util.ArrayList;
import java.util.List;public class Test11 { public static void writemethod(File file, InputStreamReader ips)
throws IOException {
FileWriter fw = new FileWriter(file);
if (!file.exists()) {
file.createNewFile();
}
int i;
while ((i = ips.read()) != 13) {
fw.write((char) i);
}
fw.close();
ips.close();
} public static int readmethod(File file) throws IOException {
FileReader fr = new FileReader(file);
int i;
List<String> list = new ArrayList<String>();
while ((i = fr.read()) != -1) {
String val = "";
while (i != 32&i != -1) {
val = val + (char) i;
i = fr.read();
}
list.add(val);
}
int sum = 0;
for (String v : list) {
int kk = Integer.parseInt(v);
sum = sum + kk;
}
return sum / list.size();
} public static void main(String[] args) throws IOException {
InputStreamReader ips = new InputStreamReader(System.in);
File file = new File("f://test3.txt");
writemethod(file, ips);
System.out.println(readmethod(file)); }
}