我将我的java文件设置为计算电话帐单并以此格式打印到控制台。
Invoice
--------------------------
Account Amount Due
10011 $12.25
10033 $11.70
--------------------------
Total $23.95
但是当我运行程序时，我只在文本文件
上得到这个Account Amount_Due
10011 $12.25
10033 $11.7
有人可以帮我编辑正确格式的文件创建代码吗？
import java.io.BufferedReader;
import java.io.BufferedWriter;
import java.io.File;
import java.io.FileInputStream;
import java.io.FileReader;
import java.io.FileWriter;
import java.io.IOException;
import java.io.InputStream;
import java.io.InputStreamReader;
import java.text.DecimalFormat;
import java.util.ArrayList;
import java.util.StringTokenizer;
import java.util.Vector;
public class PhoneBill {
Vector data;
Vector processed = new Vector();
Vector markProcessed = new Vector();
public void readFile(String inFileStr)
{
String str = "";
data = new Vector<LineItem>();
FileReader fReader;
InputStream inFileStream;
try{
fReader = new FileReader(inFileStr);
BufferedReader br=new BufferedReader(fReader);
String line;
while ((line=br.readLine())!= null){
if (line.indexOf("_") != -1)
continue;
else
if (!line.isEmpty()){
data.add(new LineItem(line.trim()));
}
}
br.close();
}
catch (Exception e){
}
}
public void processCharges()
{
String out = "Account Amount_Due\n";
System.out.println ("Invoice");
System.out.println ("--------------------------");
System.out.println ("Account " + "Amount Due ");
double total = 0.0;
double lCharges =0;
boolean done = false;
DecimalFormat numFormatter = new DecimalFormat("$##.##");
for (int j = 0; j < data.size(); j++ ){
LineItem li = (LineItem)data.get(j);
String accNum = li.getAccountNum();
if (j > 0){
done = checkProcessed(accNum);}
else
processed.add(accNum);
if (!done){
lCharges = 0;
for (int i = 0; i < data.size(); i++){
String acc = ((LineItem)data.get(i)).getAccountNum();
if (acc.equals(accNum) && !done)
lCharges += processItemCharges(accNum);
done = checkProcessed(accNum);
}
lCharges+=10.0;
System.out.format ("%s" + " $%.2f%n",accNum, lCharges);
out += accNum+" ";
out += numFormatter.format(lCharges)+"\n";
processed.add(accNum);
total += lCharges;
}
}
System.out.println ("--------------------------");
System.out.format ("%s" + " $%.2f%n","Total", total);
writeToFile("invoice.txt", out);
}
private void writeToFile(String filename,String outStr)
{
try{
File file = new File(filename);
// if file doesnt exists, then create it
if (!file.exists()) {
file.createNewFile();
}
FileWriter fw = new FileWriter(file.getAbsoluteFile());
BufferedWriter bw = new BufferedWriter(fw);
bw.write(outStr);
bw.close();
} catch (IOException ioe){
System.out.println(ioe.getMessage());
}
}
private boolean checkProcessed(String accNum){
if (processed.contains(accNum))
return true;
else
return false;
}
private double processItemCharges(String accNum)
{
double charges = 0.0;
for (int i = 0; i < data.size(); i++)
{
if(((LineItem)data.get(i)).getAccountNum().equals(accNum))
charges += ((LineItem)data.get(i)).getCharges();
}
return charges;
}
public static void main(String[] args)
{
PhoneBill pB = new PhoneBill();
pB.readFile("input_data.txt");
pB.processCharges();
}
class LineItem{
String accNum ;
String timeOfCall;
double mins;
double amountDue;
boolean counted = false;
public LineItem(String accStr)
{
processAccount(accStr);
}
private void processAccount(String accStr){
StringTokenizer st = new StringTokenizer(accStr);
accNum = (String)st.nextElement();
timeOfCall = (String) st.nextElement();
mins = Double.parseDouble((String) st.nextElement());
if (timeOfCall.compareTo("08:00")>0 && timeOfCall.compareTo("22:00")<0)
amountDue = mins*0.10;
else
amountDue = mins*0.05;
}
public String getAccountNum()
{
return accNum;
}
public double getCharges()
{
return amountDue;
}
}
}
答案 0 :(得分：0)
打印到控制台（即System.out.println）与连接out变量（即out + =）不同。
所以当你打电话
writeToFile("invoice.txt", out);
您只是将字符串'out'中的内容写入文件。如果你回顾一下你的代码，你会发现所有缺失的行只会被打印到控制台，但不能连接到'out'变量。纠正这一点，你不应该有问题。
答案 1 :(得分：0)
研究这个。它使用了更高级的Java，但理解它将非常适合您。
package test;
import java.io.*;
import java.util.*;
public class PhoneBill {
private static String BILL_FORMAT = "%-10s $%,6.2f\n";
private static boolean DEBUG=true;
Map<String, List<LineItem>> accounts = new HashMap<String,List<LineItem>>();
public void readFile(String inFileStr) {
FileReader fReader=null;
try {
fReader = new FileReader(inFileStr);
BufferedReader br = new BufferedReader(fReader);
String line;
while ((line = br.readLine()) != null) {
if (line.indexOf("_") != -1)
continue;
else if (!line.isEmpty()) {
LineItem li = new LineItem(line.trim());
List<LineItem> list = accounts.get(li.accNum);
if(list==null){
list = new ArrayList<LineItem>();
accounts.put(li.accNum, list);
}
list.add(li);
}
}
br.close();
} catch (Exception e) {
/* Don't just swallow Exceptions. */
e.printStackTrace();
} finally {
if(fReader!=null){
try{
fReader.close();
} catch(Exception e){
e.printStackTrace();
}
}
}
}
public void processCharges() {
StringBuffer out = new StringBuffer(100)
.append("Invoice\n")
.append("--------------------------\n")
.append("Account Amount Due \n");
double total = 0.0;
double lCharges = 0;
for (String accNum:accounts.keySet()) {
List<LineItem> account = accounts.get(accNum);
lCharges = 10;
for(LineItem li:account){
lCharges += li.getCharges();
}
total += lCharges;
out.append(String.format(BILL_FORMAT, accNum, lCharges));
}
out.append("--------------------------\n");
out.append(String.format(BILL_FORMAT, "Total", total));
writeToFile("invoice.txt", out.toString());
}
private void writeToFile(String filename, String outStr) {
if(DEBUG){
System.out.printf("========%swriteToFile:%s=========\n", '=', filename);
System.out.println(outStr);
System.out.printf("========%swriteToFile:%s=========\n", '/', filename);
}
try {
File file = new File(filename);
// If file doesn't exist, then create it.
if (!file.exists()) {
file.createNewFile();
}
FileWriter fw = new FileWriter(file.getAbsoluteFile());
BufferedWriter bw = new BufferedWriter(fw);
bw.write(outStr);
bw.close();
} catch (IOException ioe) {
System.out.println(ioe.getMessage());
}
}
public static void main(String[] args) {
PhoneBill pB = new PhoneBill();
pB.readFile("input_data.txt");
pB.processCharges();
}
static class LineItem {
String accNum;
double timeOfCall;
double mins;
double amountDue;
boolean counted = false;
private static final double EIGHT_AM = convertTime("08:00");
private static final double TEN_PM = convertTime("22:00");
public LineItem(String accStr) {
processAccount(accStr);
}
private void processAccount(String accStr) {
StringTokenizer st = new StringTokenizer(accStr);
accNum = st.nextToken();
timeOfCall = convertTime(st.nextToken());
mins = Double.parseDouble(st.nextToken());
if (timeOfCall > EIGHT_AM && timeOfCall < TEN_PM)
amountDue = mins * 0.10;
else
amountDue = mins * 0.05;
}
public String getAccountNum() {
return accNum;
}
public double getCharges() {
return amountDue;
}
private static double convertTime(String in){
/* Will blow up if `in` isn't given in h:m. */
String[] h_m = in.split(":");
return Double.parseDouble(h_m[0])*60+Double.parseDouble(h_m[1]);
}
}
}