这是我的第一个多线程应用程序,我遇到了一些困难。我正在创建一个名为TextDistanceThread类的新对象,它实现了Runnable,但是当我尝试调用start()时,编辑器告诉我没有这样的方法,并且文件不会编译。这是我的Driver类:
public class Driver {
static float [][] results = new float[30][6];
public static void main(String [] args) throws FileNotFoundException {
Runnable [] threads = new TextDistanceThread[180];
int threadCount = 0;
for(int i = 0 ; i < 30 ; i++) {
threads[threadCount] = new TextDistanceThread("Macbeth.txt", "Othello.txt", i, 0);
threads[threadCount++].start();
threads[threadCount] = new TextDistanceThread("Macbeth.txt", "HuckFinn.txt", i, 1);
threads[threadCount++].start();
threads[threadCount] = new TextDistanceThread("Macbeth.txt", "TomSawyer.txt", i, 2);
threads[threadCount++].start();
threads[threadCount] = new TextDistanceThread("Othello.txt", "HuckFinn.txt", i, 3);
threads[threadCount++].start();
threads[threadCount] = new TextDistanceThread("Othello.txt", "TomSawyer.txt", i, 4);
threads[threadCount++].start();
threads[threadCount] = new TextDistanceThread("TomSawyer.txt", "HuckFinn.txt", i, 5);
threads[threadCount++].start();
}
}
}
这里是TextDistanceThread类: 公共类TextDistanceThread实现Runnable {
final int numTexts;
Dictionary<String, Integer>[] texts;
Dictionary<String, Float>[] normalized;
float difference;
int [] lengths;
int row, col;
public TextDistanceThread(String file1, String file2, int row, int col) throws FileNotFoundException {
numTexts = 2;
texts = new Dictionary[numTexts];
normalized = new Dictionary[numTexts];
for (int text = 0 ; text < numTexts ; text++) {
texts[text] = new Dictionary<String, Integer>();
normalized[text] = new Dictionary<String, Float>();
}
difference = 0;
lengths = new int[numTexts];
this.row = row;
this.col = col;
//Read file into dictionary without punctuation
if(new File(file1).exists()) {System.out.println("File " + file1 + " found");}
Scanner text = new Scanner(new File(file1));
while (text.hasNext()) {
lengths[0]++;
String temp = text.next().toLowerCase().replaceAll("(?!\')\\p{Punct}", "");
if (!texts[0].add(temp, 1)) {
texts[0].set(temp, texts[0].lookup(temp) + 1);
}
}
if(new File(file2).exists()) {System.out.println("File " + file2 + " found");}
text = new Scanner(new File(file2));
while (text.hasNext()) {
lengths[1]++;
String temp = text.next().toLowerCase().replaceAll("(?!\')\\p{Punct}", "");
if (!texts[1].add(temp, 1)) {
texts[1].set(temp, texts[1].lookup(temp) + 1);
}
}
}
public void run() {
System.out.println("Normalizing:");
//Normalize dictionaries
for(int i = 0 ; i < numTexts ; i++) {
texts[i].reset();
normalized[i].add((String) texts[i].getCurrentPair().getKey(), (float)texts[i].getCurrent() / lengths[i]);
while(texts[i].hasNext()) {
texts[i].next();
normalized[i].add((String) texts[i].getCurrentPair().getKey(), (float)texts[i].getCurrent() / lengths[i]);
}
}
//Find the difference
texts[0].reset();
System.out.println("Cross-checking:");
while(normalized[0].hasNext()) {
if(normalized[1].contains(normalized[0].getCurrentPair().getKey())) {
difference += Math.abs(normalized[0].getCurrent() - normalized[1].lookup((String)normalized[0].getCurrentPair().getKey()));
//System.out.println(normalized[0].getCurrentPair() + Float.toString(Math.abs(normalized[0].getCurrent() - normalized[1].lookup((String) normalized[0].getCurrentPair().getKey()))));
normalized[1].remove(normalized[0].getCurrentPair().getKey());
normalized[0].remove();
normalized[0].reset();
}
else {
normalized[0].next();
}
}
System.out.println("Adding:");
for(int i = 0 ; i < numTexts ; i++) {
normalized[i].reset();
difference += normalized[i].getCurrent();
//System.out.println(normalized[i].getCurrentPair() + Float.toString(normalized[i].getCurrent()));
while(normalized[i].hasNext()) {
difference += Math.abs(normalized[i].getNext());
//System.out.println(normalized[i].getCurrentPair() + Float.toString(normalized[i].getCurrent()));
}
}
Driver.results[row][col] = difference;
}
}
我试着在各地搜索谷歌,似乎没有其他人遇到这个问题。我确信我错过了一些非常明显的东西。
另外,我应该知道有关安排的事情吗?
答案 0 :(得分:2)
Runnable
界面并未声明start()
方法。这就是你无法召唤它的原因。
使用Runnable
启动主题的标准方法是将Runnable
实例传递给Thread
,并在start()
上调用Thread
。
创建一个Thread
数组,使用Thread
创建Runnable
,然后在这些start()
上调用Thread
。
Thread[] threads = new Thread[180];
E.g。
threads[threadCount] = new Thread(
new TextDistanceThread("Macbeth.txt", "Othello.txt", i, 0));
JVM负责为您安排线程;你不必担心安排它们。
答案 1 :(得分:2)
由于Runnable
接口没有start()
方法。您应该将Runnable
实例传递给Thread
。您可以使用
new Thread(threads[threadCount++]).start();