軟件源代碼清單

*由于源代碼太長，這里只貼出核心搜索線程SearchThread的源代碼，其它代碼請參看：JSApplet.java和SearchThread.java

SearchThread.java
/*
 *   JSearch - turns search Engines into FIND engines - Programming in JAVA
 *   Copyright (C) 1999-2002  Hunt Lin
 *
 *   This program is free software; you can redistribute it and/or modify
 *   it under the terms of the GNU General Public License as published by
 *   the Free Software Foundation; either version 2 of the License, or
 *   (at your option) any later version.
 *
 *   This program is distributed in the hope that it will be useful,
 *   but WITHOUT ANY WARRANTY; without even the implied warranty of
 *   MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
 *   GNU General Public License for more details.
 *
 *   You should have received a copy of the GNU General Public License
 *   along with this program; if not, write to the Free Software
 *   Foundation, Inc., 675 Mass Ave, Cambridge, MA 02139, USA.
 *
 *   Also add information on how to contact you by electronic and paper mail.
 */
 
import java.io.*;
import java.net.*;

public class SearchThread extends Thread {

	//要搜索的內容
	String srchChainConverted;
	//當前搜索線程的序號
	int srchNo;
	//搜索引擎的基本信息
	String srchBlkB, srchBlkE, srchEngName;
	
	//定義搜索當中要用到的變量
	String srchChainConvertedWithLevel;			//加入Level后的搜索串
	BufferedReader inURLStream;					
	char matchChars[]	= {' ', ' ', ' ', ' '};	//將與標志相符的字符
	char singleChar[]	= {' '};				//每次取得的字符
	String matchString;							//用作matchChars到String的轉化。
	int resultCount		= 0;					//當前線程找到的結果

	//準備搜集的信息
	String			resultDtlHead	= new String();			//用于存放結果集中的URL
	ResultsDetails	resultDtlBody	= new ResultsDetails();	//用于存放主題和預覽
	
	//核心搜索線程
	public void run() {
		try {
			for (int level=0; level < Integer.valueOf(JSApplet.smlCh.getSelectedItem()).intValue() && !JSApplet._stop; level++) {
				
				//用級數處理搜索串
				srchChainConvertedWithLevel = srchChainConverted.replace('`',(char)(48+level));
				//打開搜索的頁面流
				inURLStream = new BufferedReader(new InputStreamReader((new URL(srchChainConvertedWithLevel)).openStream()));
				//推進
				while (stepOneChar()) {
					//找到信息塊的開始：srchBlkB
					if (matchString.equals(srchBlkB)) {
						
						//準備收集信息
 						resultDtlHead = "";
						resultDtlBody.title = "";
						resultDtlBody.preview = "";

						//對信息塊進行分析，并取出URL，TITLE，PREVIEW
						analyseBlock();
						
						//將最后一個非結果集排除，因為最后一個信息塊的結束不可能也是頁面的結束。或如果當頁已結束則退出。
						if (!stepOneChar()) break;
						
						//適當休眠，讓PREVIEW有辦法進行！且讓其它搜索線程有辦法進行！并讓死鎖有時間釋放。并且如果有多個線程，這0.1秒的重疊后也就不算什么了。
						Thread.sleep(100);
						
						//對所得到的結果進行網址有效性驗證
						if (JSApplet.valurlCh.getSelectedItem().equals("Yes")) {
							if (!validUrl()) break;	//如果驗證不通過，則不將這個URL記入/顯示。
						}

						//將結果存放并顯示
						showResult();
						
					} //if
				} //while
				
				//關閉流
				inURLStream.close();
			}
			
		} catch(Exception ex) {
			JSApplet.messageTe.append("Exception: '" + ex.toString() + "' in SearchThread.run().\n");
		}
		
		//將活動連接減一，并適時地置按鈕的狀態。
		if (--JSApplet.actualSearchAllowed == 0) {
			JSApplet.buttonStatus(2);
			JSApplet._stop = true;
		}
	}
	
	//用傳入的變量對類中的變量進行賦值
	public SearchThread(String srchChainConverted, String srchBlkB, String srchBlkE, String srchEngName, int srchNo) {
		this.srchChainConverted	= srchChainConverted;
		this.srchBlkB			= srchBlkB;
		this.srchBlkE			= srchBlkE;
		this.srchEngName		= srchEngName;
		this.srchNo				= srchNo;
	}
	
	//向前推進一個字符
	boolean stepOneChar() {
		boolean _step = false;
		try {
			if (inURLStream.read(singleChar,0,1) != -1 && !JSApplet._stop) {
				matchChars[0]	= matchChars[1]; 
				matchChars[1]	= matchChars[2]; 
				matchChars[2]	= matchChars[3];
				matchChars[3]	= singleChar[0];
				matchString		= new String(matchChars); //不能用toString()！！！
				_step = true;
			}
		} catch(Exception ex) {
			JSApplet.messageTe.append("Exception: '" + ex.toString() + "' in SearchThread.stepOneChar().\n");
		}
		return _step;
	}

	
	//分析信息塊
	void analyseBlock() {
		/////取得網址
		//找到網址標志
		while (!matchString.equals("ref=")) {
			if (!stepOneChar()) break;
		};
		//跳過第一個'='
		if (!stepOneChar()) return;
		//處理并得到網址，主要是去掉"\""（引號）
		while (singleChar[0] != '>' && singleChar[0] != ' ') {
			//向前推進一個字符
			if (singleChar[0] != '\"') resultDtlHead += singleChar[0];
			if (!stepOneChar()) break;
		}
						
		//處理由于遇到' '提前退出時，繼續處理至'>'
		while (singleChar[0] != '>') {
			//向前推進一個字符
			if (!stepOneChar()) break;
		}
						
		/////取得標題
		//當遇到"</a>"結束。
		while (!matchString.equals("</a>")) {
			if (!stepOneChar()) break;
			//過濾"<"和">"之間的內容。
			if (singleChar[0] == '<') {
				while (singleChar[0] != '>') {
					if (!stepOneChar()) break;
				}
			}
			if (singleChar[0] != '>') resultDtlBody.title += singleChar[0];
		}
						
		/////取得預覽
		while (!matchString.equals(srchBlkE)) {
			if (!stepOneChar()) break;
			//過濾"<"和">"之間的內容。
			if (singleChar[0] == '<') {
				while (singleChar[0] != '>') {
					if (!stepOneChar()) break;
				}
			}
			if (singleChar[0] != '>' && singleChar[0] != '\r' && singleChar[0] != '\n') resultDtlBody.preview += singleChar[0];
		}
	}
	
	//網址有效性驗證
	boolean validUrl() {
		boolean vldOk = false;
		try {
			(new BufferedReader(new InputStreamReader((new URL(resultDtlHead)).openStream()))).close();
			vldOk = true;
		} catch(Exception ex) {
			JSApplet.messageTe.append("Exception: '" + ex.toString() + "' in SearchThread.validUrl().\n");
		}
		return vldOk;
	}

	//格式化結果集
	String formatString(String unFmtStr, int width) {
		String fmtStr;								//要返回的格式化的字符串。
		byte unFmtBytes[] = unFmtStr.getBytes();	//按byte對unFmtStr進行處理
		if (unFmtBytes.length > width) {
			fmtStr = new String(unFmtBytes, 0, width);
			//處理漢字可能被中間截斷的情況。
			if ((fmtStr.equals("")) || (fmtStr.getBytes().length < width)) fmtStr = (new String(unFmtBytes, 0, width-1)) + " ";
		} else {
			String addSpaces = "";	//需要填充的字符。
			for (int i = unFmtBytes.length; i < width; i ++) addSpaces += " ";
			fmtStr = unFmtStr + addSpaces;
		}
		return fmtStr;
	}
	
	//顯示結果信息
	void showResult() {
		synchronized (JSApplet.resultTable) {synchronized (JSApplet.resultIndex) {synchronized (JSApplet.resultLi) {synchronized (JSApplet.statusLi) {synchronized (JSApplet.totalNumLa) {
			if (!JSApplet.resultTable.containsKey(resultDtlHead) && !JSApplet.resultIndex.contains(resultDtlHead)) {
				
				//一定要新建一個才能放進HashTable中！
				ResultsDetails resultDtlBody	= new ResultsDetails();
				resultDtlBody.title				= this.resultDtlBody.title;
				resultDtlBody.preview			= this.resultDtlBody.preview;
				
				//將結果放入JSApplet的resultTable/resultIndex中共用。
				JSApplet.resultTable.put(resultDtlHead, resultDtlBody);	//必須要用獨立的resultDtlBody對象才能放入HashTable
				JSApplet.resultIndex.addElement(resultDtlHead);
								
				//將結果顯示于JSApplet中，要對所得結果用formatString進行必要的格式化。
				JSApplet.resultLi.add(formatString(resultDtlBody.title, 42) + " | " + formatString(resultDtlHead, 40) + " | from: " + srchEngName);
				JSApplet.totalNumLa.setText(String.valueOf(Integer.valueOf(JSApplet.totalNumLa.getText()).intValue() + 1));
								
				//在STATUS中顯示當前搜索狀況
				JSApplet.statusLi.replaceItem("Results:" + String.valueOf(++resultCount) + " From:" + srchEngName + " Received.", srchNo);
			}
		}}}}}
	}
	
	//析構函數
	public void finalize() throws Throwable {
		try {
			//人工退出，要將inURLStream關閉
			if (this != null) if (inURLStream != null) inURLStream.close();
		} catch (Exception ex) {
			JSApplet.messageTe.append("Exception: '" + ex.toString() + "' in SearchThread.finalize().\n");
		}
		super.finalize();
		System.gc();
		System.runFinalization();
	}
}