当前代码是单线程的。它从文件中读取数据，生成随机数并检查这些数字是否属于给定的区间。
import java.io.*;
import java.util.*;
class Generator {
private double mean;
private double variance;
private long amountOfNumbersToGenerate;
public Generator(double mean, double variance, long amountOfNumbersToGenerate) {
this.mean = mean;
this.variance = variance;
this.amountOfNumbersToGenerate = amountOfNumbersToGenerate;
}
double getMean() {
return mean;
}
double getVariance() {
return variance;
}
long getAmountOfNumbersToGenerate() {
return amountOfNumbersToGenerate;
}
}
class Interval {
private double start;
private double end;
public Interval(double start, double end) {
this.start = start;
this.end = end;
}
double getStart() {
return start;
}
double getEnd() {
return end;
}
}
class ParsedData {
private Vector<Generator> generators;
private Vector<Interval> intervals;
public ParsedData(Vector<Generator> generators, Vector<Interval> intervals) {
this.generators = generators;
this.intervals = intervals;
}
Vector<Generator> getGenerators() {
return generators;
}
Vector<Interval> getIntervals() {
return intervals;
}
}
class Worker extends Thread {
public Worker() {
}
}
class Start {
static ParsedData readDataFromFile(String path) throws IOException {
File file = new File(path);
BufferedReader br = new BufferedReader(new FileReader(file));
String line;
line = br.readLine();
String delimiter = "\\s+";
// generators
long generatorSize = Long.parseLong(line);
Vector<Generator> generators = new Vector<Generator>();
for(long i =0; i < generatorSize; i++) {
line = br.readLine();
Scanner f = new Scanner(line);
f.useLocale(Locale.US); //without this line the program wouldn't work on machines with different locales
f.useDelimiter(delimiter);
Generator g = new Generator(f.nextDouble(), f.nextDouble(), f.nextInt());
generators.add(g);
}
line = br.readLine();
long intervalSize = Long.parseLong(line);
Vector<Interval> intervals = new Vector<Interval>();
for(long i = 0; i < intervalSize; i++) {
line = br.readLine();
System.out.println(line);
Scanner f = new Scanner(line);
f.useLocale(Locale.US); //without this line the program wouldn't work on machines with different locales
f.useDelimiter(delimiter);
Interval interval = new Interval(f.nextDouble(), f.nextDouble());
intervals.add(interval);
}
br.close();
return new ParsedData(generators, intervals);
}
static double boxMullerMarsagliaPolarRand(double mean, double variance) {
double micro = mean;
double sigma = Math.sqrt(variance);
double y, x, omega;
Random random = new Random();
do {
x = random.nextDouble();
y = random.nextDouble();
omega = x * x + y * y;
} while (!(0.0 < omega && omega < 1.0));
double sigma_sqrt = sigma * Math.sqrt(-2.0 * Math.log(omega) / omega);
double g = micro + x * sigma_sqrt;
// float h = micro + y * sigma_sqrt;
return g;
}
/////////////////////////////////////////
// TODO: refactor code into multithreaded
static Vector<Double> generateRandomNumbers(ParsedData parsedData) {
Vector<Double> generatedNumbers = new Vector<Double>();
for(int i = 0; i < parsedData.getGenerators().size(); i++) {
Generator g = parsedData.getGenerators().get(i);
for(long j = 0; j < g.getAmountOfNumbersToGenerate(); j++) {
double random = boxMullerMarsagliaPolarRand(g.getMean(), g.getVariance());
generatedNumbers.add(random);
}
}
return generatedNumbers;
}
/////////////////////////////////////////
// TODO: refactor code into multithreaded
static int[] checkIntervals(ParsedData parsedData, Vector<Double> generatedNumbers) {
int[] numberOfHits = new int[parsedData.getIntervals().size()];
for(int j = 0; j < parsedData.getIntervals().size(); j++) {
Interval interval = parsedData.getIntervals().get(j);
for(int i = 0; i < generatedNumbers.size(); i++) {
if (interval.getStart() < generatedNumbers.get(i) && generatedNumbers.get(i) < interval.getEnd()) {
numberOfHits[j]++;
}
}
}
return numberOfHits;
}
public static void main(String args[]) {
int amountOfThreads = Integer.parseInt(args[0]);
String path = System.getProperty("user.dir") + "/input.dat";
ParsedData parsedData = null;
try {
parsedData = readDataFromFile(path);
} catch (IOException e) {
e.printStackTrace();
}
System.out.println(parsedData.getGenerators().size());
System.out.println(parsedData.getIntervals().size());
Vector<Double> generatedNumbers = generateRandomNumbers(parsedData);
int[] numberOfHits = checkIntervals(parsedData, generatedNumbers);
for (int i = 0; i < numberOfHits.length; i++) {
Interval interval = parsedData.getIntervals().get(i);
System.out.println("" + (i+1) + " " + interval.getStart() + " " + interval.getEnd() + " " + numberOfHits[i]);
}
System.out.println(generatedNumbers.size());
}
}
我不希望任何人为我编写/重构代码。
但我不知道如何使这个方法多线程：
/////////////////////////////////////////
// TODO: refactor code into multithreaded
static Vector<Double> generateRandomNumbers(ParsedData parsedData) {
Vector<Double> generatedNumbers = new Vector<Double>();
for(int i = 0; i < parsedData.getGenerators().size(); i++) {
Generator g = parsedData.getGenerators().get(i);
for(long j = 0; j < g.getAmountOfNumbersToGenerate(); j++) {
double random = boxMullerMarsagliaPolarRand(g.getMean(), g.getVariance());
generatedNumbers.add(random);
}
}
return generatedNumbers;
}
/////////////////////////////////////////
// TODO: refactor code into multithreaded
static int[] checkIntervals(ParsedData parsedData, Vector<Double> generatedNumbers) {
int[] numberOfHits = new int[parsedData.getIntervals().size()];
for(int j = 0; j < parsedData.getIntervals().size(); j++) {
Interval interval = parsedData.getIntervals().get(j);
for(int i = 0; i < generatedNumbers.size(); i++) {
if (interval.getStart() < generatedNumbers.get(i) && generatedNumbers.get(i) < interval.getEnd()) {
numberOfHits[j]++;
}
}
}
return numberOfHits;
}