抽象模型，严谨代码，开源分享

缺乏、安全感 2022-03-11 14:35 142阅读 0赞

前言  
首先，感谢Eric对我代码上的建议，感谢Stone在FTP Lab环境部署上对我的指导。  
  
今年4月份的时候，做了一个小的项目，当时也没有去总结整理，现在想想总结整理是很有必要的，这也是一个很好的工作研究的习惯。  
  
关于项目，不论大小，其实做到极致也不是一件容易的事。只有做到极致，才算真正的项目经验；只有做到极致，才能让编程真正成为一门艺术；只有体会编程是一门有趣的艺术时，你的职业生涯才经久不衰，常青不老。  
  
当然，我现在也只是一个走在编程艺术道路上的小孩，不停探索，充满好奇，我也希望志同道合的同仁们给我指教与分享。  
  
我相信，只有开源了，才会有更多更大的进步，才会有活力，有创造力。我支持开源与自由，我唾弃陈旧死板的开发与管理！  
  
交流方式：【E-Mail】 zhoushengshuai2007@163.com 【QQ】 254392398  
  
  
项目简介  
略......  
  
编程点滴  
1. 同样一个文件能只打开一次搞定的，就只打开一次，避免频繁的I/O流操作。比如：读一个属性文件，文件中有很多属性项目，我们可以将属性项预定义在一个数组里，当打开属性文件时，遍历属性数组，将得到的属性键值对预存在一个哈希表里，这样之后在用到属性值时，只需从哈希表里获取就可以了。

String[] propertyArray = new String[] { "templateDirectory", "sourceDirectory", "cm",
    				"filereadyfile", "xmlCMIRPVersion", "expireHour",
    				"meLimitCount", "fileNamePrefix", "subObjectLimitCount" };
    
    		Map<String, String> propertyMap = CommonTool.getPropertyMap(ConstantPool.CM_CONFIGRATION_FILE, propertyArray);

public static Map<String, String> getPropertyMap(String cmccCmConfigurationFile, String[] propertyArray) {
       
    		InputStream inputStream = null;
    
    		Map<String, String> propertyMap = new HashMap<String, String>();
    		int propertyArrayLength = propertyArray.length;
    
    		Properties properties = new Properties();
    
    		try {
       
    			inputStream = Files.newInputStream(Paths.get(cmccCmConfigurationFile));
    			properties.load(inputStream);
    		} catch (IOException ioe) {
       
    			LOG.error(ioe.getMessage());
    			ioe.printStackTrace();
    		} finally {
       
    			IOUtils.closeQuietly(inputStream);
    		}
    
    		for (int index = 0; index < propertyArrayLength; index++) {
       
    			String propertyName = propertyArray[index];
    			String propertyValue = properties.getProperty(propertyName);
    
    			if (StringUtils.trimToEmpty(propertyValue).equals("")) {
       
    				throw new NullPointerException("There is no property " + propertyName + " in the configuration file " + cmccCmConfigurationFile);
    			} else {
       
    				propertyValue = StringUtils.trim(propertyValue);
    			}
    
    			propertyMap.put(propertyName, propertyValue);
    		}
    
    		return propertyMap;
    	}

2. 我们能计算一次搞定的，就只计算一次，比如：我们会经常遍历数组，往往会让数组长度的计算在循环中计算多次，这是低效的。

int propertyArrayLength = propertyArray.length;
    
    		for (int index = 0; index < propertyArrayLength; index++) {
       
    			......
    		}

for (int index = 0; index < propertyArray.length; index++) {
       
    			......
    		}

3. 我们处理属性文件时，一定要严谨，比如：有个属性项是表示数量的，当我们获取到该属性项时，我们要对其进行数字正则判断，要不然你得到一个非数字的属性，你怎么拿来运算？

public static boolean isDigit(String str) {
       
    		boolean isDigitFlag = false;
    
    		if (str.matches("(^[-|+]?)\\d+")) {
       
    			isDigitFlag = true;
    		}
    
    		return isDigitFlag;
    	}

4. 我们经常会拼凑，传参等方式来定义文件名，所以在这种情况下，有必要对文件名合法性与否作出正则判断。

public static boolean isInvalidFileName(String fileName) {
       
    		boolean isInvalidFileNameFlag = false;
    
    		if (fileName.matches(".*[\\/:\\*\\?\"<>\\|].*")) {
       
    			isInvalidFileNameFlag = true;
    		}
    
    		return isInvalidFileNameFlag;
    	}

5. 我们对特殊字符的处理，也要严谨，考虑方方面面，比如：在文件中将'&'转换成'&'，'<'转换成'<'，'>'转换成'>'，在这种情况下，你就不能将'&'和'<'，以及'>'中的'&'再转换成'&'了。

public static String replaceReserveSymbel(String convertPartStr) {
       
    		if (convertPartStr != null) {
       
    			if (convertPartStr.contains("&")) {
       
    				StringBuffer sb = new StringBuffer("");
    				convertPartStr = replaceReserveSymbel(convertPartStr, sb);
    			}
    
    			convertPartStr = convertPartStr.replace("<", "<");
    			convertPartStr = convertPartStr.replace(">", ">");
    
    			convertPartStr = convertPartStr.replace("\\", "\\\\");
    			convertPartStr = convertPartStr.replace("{", "\\{");
    			convertPartStr = convertPartStr.replace("}", "\\}");
    			convertPartStr = convertPartStr.replace("(", "\$");
    			convertPartStr = convertPartStr.replace(")", "\$");
    			convertPartStr = convertPartStr.replace(",", "\\,");
    		}
    
    		return convertPartStr;
    	}
    
    	public static String replaceReserveSymbel(String convertPartStr, StringBuffer sb) {
       
    		int index = convertPartStr.indexOf("&");
    
    		String leftStr = "";
    		String rightStr = "";
    
    		if (index >= 0) {
       
    			leftStr = convertPartStr.substring(0, index + 1);
    			rightStr = convertPartStr.substring(index + 1);
    
    			sb.append(leftStr);
    
    			if (!rightStr.startsWith("amp;") && !rightStr.startsWith("lt;") && !rightStr.startsWith("gt;")) {
       
    				sb.append("amp;");
    			}
    
    			replaceReserveSymbel(rightStr, sb);
    		} else {
       
    			sb.append(convertPartStr);
    		}
    
    		return sb.toString();
    	}

6. 在多线程编程中，我们很多时候要实现接口Callable<?>, 而非实现接口Runnable,接口Callable<?>给我们带来的方便是不言而喻的，因为，可以重写它的方法call()，获得我们想要的返回值。

/**
     * @author shengshu
     * 
     */
    public class ConverterTask implements Callable<File> {
       
    	private static final Logger LOG = Logger.getLogger(ConverterTask.class);
    
    	private File templateFile = null;
    	private File fragmentFile = null;
    	private String exportDirectoryStr = null;
    	private String notificationDirectoryStr = null;
    
    	public String fileNamePrefix = null;
    
    	private static final Date date = new Date();
    
    	public ConverterTask(File fragmentFile, File templateFile, String destDirectoryStr, String notificationDirectoryStr, String fileNamePrefix) {
       
    		this.fragmentFile = fragmentFile;
    		this.templateFile = templateFile;
    		this.exportDirectoryStr = destDirectoryStr;
    		this.notificationDirectoryStr = notificationDirectoryStr;
    
    		this.fileNamePrefix = fileNamePrefix;
    	}
    
    	public File convertFile(File fragmentFile, File templateFile, String exportDirectoryStr, String notificationDirectoryStr, String fileNamePrefix) {
       
    
    		......
    
    		return exportFile;
    	}
    
    	public void convertFile(File fragmentFile, File templateFile, File exportDirectory, File notificationDirectory, String fileNamePrefix) throws Throwable {
       
    		convertFile(fragmentFile, templateFile, exportDirectory.getAbsolutePath(), notificationDirectory.getAbsolutePath(), fileNamePrefix);
    	}
    
    	@Override
    	public File call() throws Exception {
       
    		File exportFile = convertFile(fragmentFile, templateFile, exportDirectoryStr, notificationDirectoryStr, fileNamePrefix);
    
    		return exportFile;
    	}
    
    }

private static void initConverter() {
       
    		LOG.info("Converter thread pool size: " + threadPoolSize);
    		converterThreadPool = Executors.newFixedThreadPool(threadPoolSize);
    
    		converterFutureList = new ArrayList<Future<File>>();
    
    		if (sourceDirectory != null && sourceDirectory.isDirectory()) {
       
    			fragmentFileCollection = FileUtils.listFiles(sourceDirectory, new String[] { "xml", "XML" }, false);
    		} else {
       
    			LOG.warn("The directory " + sourceDirectoryStr + " doesn't exist or is invalid!");
    		}
    
    		if (templateDirectory != null && templateDirectory.isDirectory()) {
       
    			templateFileCollection = FileUtils.listFiles(templateDirectory, new String[] { "xsl", "XSL" }, false);
    		} else {
       
    			LOG.warn("The directory " + templateDirectoryStr + " doesn't exist or is invalid!");
    		}
    	}
    
    	public void converter() {
       
    		LOG.info("==================Converter Start==================");
    		startTime = System.currentTimeMillis();
    
    		initConverter();
    
    		if ((fragmentFileCollection != null && !fragmentFileCollection.isEmpty()) && (templateFileCollection != null && !templateFileCollection.isEmpty())) {
       
    
    			Iterator<File> fragmentFileIterator = fragmentFileCollection.iterator();
    
    			while (fragmentFileIterator.hasNext()) {
       
    				File fragmentFile = fragmentFileIterator.next();
    				LOG.info("Fragment file: " + fragmentFile);
    
    				Iterator<File> templateFileIterator = templateFileCollection.iterator();
    
    				while (templateFileIterator.hasNext()) {
       
    					File templateFile = templateFileIterator.next();
    					LOG.info("Template file: " + templateFile);
    
    					ConverterTask converterTask = new ConverterTask(fragmentFile, templateFile, exportDirectoryStr, notificationDirectoryStr, fileNamePrefix);
    
    					Future<File> converterFuture = converterThreadPool.submit(converterTask);
    
    					converterFutureList.add(converterFuture);
    				}
    			}
    		}
    
    		destroyConverter();
    
    		endTime = System.currentTimeMillis();
    		deltaTime = endTime - startTime;
    		LOG.info("Converter spend " + deltaTime / 1000 + " seconds");
    		LOG.info("==================Converter End==================");
    	}
    
    	private static void destroyConverter() {
       
    		LOG.info("===Start to destroy thread pool and delete files under source directory===");
    
    		for (Future<File> future : converterFutureList) {
       
    			try {
       
    				File exportFile = future.get();
    
    				if (exportFile.exists()) {
       
    					LOG.info("Invoke method call() and return : " + exportFile);
    					exportFileCollection.add(exportFile);
    				}
    			} catch (InterruptedException ie) {
       
    				ie.printStackTrace();
    			} catch (ExecutionException ee) {
       
    				ee.printStackTrace();
    			}
    		}
    
    		converterThreadPool.shutdown();
    		LOG.info("Thread pool is changed as status: SHUTDOWN");
    
    		while (!converterThreadPool.isTerminated())
    			;
    
    		LOG.info("Thread pool is changed as status: STOP");
    
    		if (!CommonTool.deleteFileCollection(fragmentFileCollection)) {
       
    			LOG.error("Fail to delete fragment files under directory " + sourceDirectoryStr);
    		}
    
    		LOG.info("===End to destroy thread pool and delete files under source directory===");
    	}

7. 我们会经常处理多线程，高并发的问题，往往会用到线程池，所以我们既要保证任务都能被执行，又能保证线程池正常终止。

subSpliterThreadPool.shutdown();
    
    		while (!subSpliterThreadPool.isTerminated())
    			;

8. 在处理XML文件时，对XSLT的应用将会大大简化我们的代码逻辑与数量，实现代码与文本处理的解耦。

<?xml version="1.0" encoding="UTF-8"?>
    
    <xsl:stylesheet version="2.0"
    	xmlns:xsl="http://www.w3.org/1999/XSL/Transform"
    	xmlns:ne="http://www.3gpp.org/ftp/specs/archive/32_series/32.615#configData"
    	xmlns:xn="http://www.3gpp.org/ftp/specs/archive/32_series/32.625#genericNrm"
    	xmlns:en="http://www.3gpp.org/ftp/specs/archive/32_series/32.765#eutranNrm">
    	<xsl:output method="xml" indent="yes" encoding="UTF-8" />
    
    	<xsl:template match="/">
    		<NrmFile xmlns:xsi="http://www.w3.org/2001/XMLSchema-instance"
    			xsi:noNamespaceSchemaLocation="NrmFileFormat.xsd">
    			<xsl:element name="FileHeader">
    				<InfoModelReferenced>CMCC-ENB-NRM-V2.1.0</InfoModelReferenced>
    				<DnPrefix>
    					<xsl:value-of select="/ne:bulkCmConfigDataFile/ne:configData/@dnPrefix" />
    				</DnPrefix>
    
    				<xsl:variable name="SystemDN"
    					select="/ne:bulkCmConfigDataFile/ne:configData/xn:SubNetwork/xn:ManagementNode/xn:IRPAgent/xn:attributes/xn:SystemDN" />
    
    				<SenderName>
    					<xsl:value-of select="$SystemDN" />
    				</SenderName>
    
    				<VendorName>
    					<xsl:value-of select="/ne:bulkCmConfigDataFile/ne:fileHeader/@vendorName" />
    				</VendorName>
    				<DateTime>
    					<xsl:value-of select="/ne:bulkCmConfigDataFile/ne:fileFooter/@dateTime" />
    				</DateTime>
    			</xsl:element>
    			<xsl:element name="Objects">
    				<ObjectType>EnbFunction</ObjectType>
    				<FieldName>
    					<N i="1">EnbId</N>
    					<N i="2">UserLabel</N>
    					<N i="3">AdministrativeState</N>
    					<N i="4">OperationalState</N>
    					<N i="5">EnbId</N>
    					<N i="6">X2IpAddressList</N>
    					<N i="7">X2BlackList</N>
    					<N i="8">X2WhiteList</N>
    					<N i="9">X2HoBlackList</N>
    					<N i="10">IntegrityProtAlgorithm</N>
    					<N i="11">CipheringAlgorithm</N>
    				</FieldName>
    				<FieldValue>
    					<xsl:for-each select="//xn:ManagedElement [*]">
    						<xsl:variable name="ManagedBy" select="xn:attributes/xn:ManagedBy" />
    						<xsl:variable name="ManagedElementID" select="@id" />
    
    						<xsl:variable name="PrefixDN">
    							<xsl:call-template name="substring-first">
    								<xsl:with-param name="text" select="$ManagedBy" />
    								<xsl:with-param name="splitor1" select="','" />
    								<xsl:with-param name="splitor2" select="'\,'" />
    							</xsl:call-template>
    						</xsl:variable>
    
    						<xsl:for-each select="en:EnbFunction[*]">
    							<xsl:variable name="EnbFunctionID" select="@id" />
    
    							<xsl:element name="Cm">
    								<xsl:attribute name="Dn">
    									<xsl:value-of
    									select="concat($PrefixDN, ',ManagedElement=',$ManagedElementID,',EnbFunction=',$EnbFunctionID)" />
    								</xsl:attribute>
    								<xsl:attribute name="UserLabel">
    									<xsl:value-of select="en:attributes/en:UserLabel" />
    								</xsl:attribute>
    
    								<V i="1">
    									<xsl:value-of select="$EnbFunctionID" />
    								</V>
    								<V i="2">
    									<xsl:value-of select="en:attributes/en:UserLabel" />
    								</V>
    								<V i="3">
    									<xsl:variable name="AdministrativeState">
    										<xsl:call-template name="translate-lowercase-uppercase">
    											<xsl:with-param name="text"
    												select="en:attributes/en:AdministrativeState" />
    										</xsl:call-template>
    									</xsl:variable>
    
    									<xsl:value-of select="$AdministrativeState" />
    								</V>
    								<V i="4">
    									<xsl:variable name="OperationalState">
    										<xsl:call-template name="translate-lowercase-uppercase">
    											<xsl:with-param name="text"
    												select="en:attributes/en:OperationalState" />
    										</xsl:call-template>
    									</xsl:variable>
    
    									<xsl:value-of select="$OperationalState" />
    								</V>
    								<V i="5">
    									<xsl:value-of select="en:attributes/en:EnbId" />
    								</V>
    								<V i="6">
    									<xsl:value-of select="'{'" />
    									<xsl:value-of select="en:attributes/en:X2IpAddressList" />
    									<xsl:value-of select="'}'" />
    								</V>
    								<V i="7">
    									<xsl:value-of select="'{'" />
    									<xsl:for-each
    										select="en:attributes/en:X2BlackList/*[starts-with(name(), 'en:EnbId')][normalize-space()]">
    										<xsl:value-of select="node()" />
    										<xsl:if test="position() < last()">
    											<xsl:value-of select="','" />
    										</xsl:if>
    									</xsl:for-each>
    									<xsl:value-of select="'}'" />
    								</V>
    								<V i="8">
    									<xsl:value-of select="'{'" />
    									<xsl:for-each
    										select="en:attributes/en:X2WhiteList/*[starts-with(name(), 'en:EnbId')][normalize-space()]">
    										<xsl:value-of select="node()" />
    										<xsl:if test="position() < last()">
    											<xsl:value-of select="','" />
    										</xsl:if>
    									</xsl:for-each>
    									<xsl:value-of select="'}'" />
    								</V>
    								<V i="9">
    									<xsl:value-of select="'{'" />
    									<xsl:for-each
    										select="en:attributes/en:X2HoBlackList/*[starts-with(name(), 'en:EnbId')][normalize-space()]">
    										<xsl:value-of select="node()" />
    										<xsl:if test="position() < last()">
    											<xsl:value-of select="','" />
    										</xsl:if>
    									</xsl:for-each>
    									<xsl:value-of select="'}'" />
    								</V>
    								<V i="10">
    									<xsl:value-of select="'{'" />
    									<xsl:for-each
    										select="en:attributes/en:IntegrityProtAlgorithm/*[starts-with(name(),'en:stringItem')][normalize-space()]">
    										<xsl:value-of select="node()" />
    										<xsl:if test="position() < last()">
    											<xsl:value-of select="','" />
    										</xsl:if>
    									</xsl:for-each>
    									<xsl:value-of select="'}'" />
    								</V>
    								<V i="11">
    									<xsl:value-of select="'{'" />
    									<xsl:for-each
    										select="en:attributes/en:CipheringAlgorithm/*[starts-with(name(),'en:stringItem')][normalize-space()]">
    										<xsl:value-of select="node()" />
    										<xsl:if test="position() < last()">
    											<xsl:value-of select="','" />
    										</xsl:if>
    									</xsl:for-each>
    									<xsl:value-of select="'}'" />
    								</V>
    							</xsl:element>
    
    						</xsl:for-each>
    					</xsl:for-each>
    				</FieldValue>
    			</xsl:element>
    		</NrmFile>
    	</xsl:template>
    
    	<xsl:template name="string-replace-all">
    		<xsl:param name="text" />
    		<xsl:param name="old" />
    		<xsl:param name="new" />
    		<xsl:choose>
    			<xsl:when test="contains($text, $old)">
    				<xsl:value-of select="substring-before($text,$old)" />
    				<xsl:value-of select="$new" />
    				<xsl:call-template name="string-replace-all">
    					<xsl:with-param name="text" select="substring-after($text,$old)" />
    					<xsl:with-param name="old" select="$old" />
    					<xsl:with-param name="new" select="$new" />
    				</xsl:call-template>
    			</xsl:when>
    			<xsl:otherwise>
    				<xsl:value-of select="$text" />
    			</xsl:otherwise>
    		</xsl:choose>
    	</xsl:template>
    
    	<xsl:template name="substring-first">
    		<xsl:param name="text" />
    		<xsl:param name="splitor1" />
    		<xsl:param name="splitor2" />
    		<xsl:choose>
    			<xsl:when test="contains($text, $splitor2)">
    				<xsl:value-of select="substring-before($text,$splitor2)" />
    			</xsl:when>
    			<xsl:otherwise>
    				<xsl:choose>
    					<xsl:when test="contains($text, $splitor1)">
    						<xsl:value-of select="substring-before($text,$splitor1)" />
    					</xsl:when>
    					<xsl:otherwise>
    						<xsl:value-of select="$text" />
    					</xsl:otherwise>
    				</xsl:choose>
    			</xsl:otherwise>
    		</xsl:choose>
    	</xsl:template>
    
    	<xsl:template name="translate-lowercase-uppercase">
    		<xsl:param name="text" />
    		<xsl:variable name="lowercase" select="'abcdefghijklmnopqrstuvwxyz'" />
    		<xsl:variable name="uppercase" select="'ABCDEFGHIJKLMNOPQRSTUVWXYZ'" />
    		<xsl:value-of select="translate($text, $lowercase, $uppercase)" />
    	</xsl:template>
    </xsl:stylesheet>

待续...