雖然現在 JSON 大法賊好,但是有時候你需要調用的接口還是 xml 格式的奧,所以這邊寫一下 dom4j 的使用,(emmmmmm 公司牆很高,只讓用 CSDN,你猜是哪家)。
這邊我使用 maven 構建工程
找到 pom.xml
<?xml version="1.0" encoding="UTF-8"?>
<project xmlns="http://maven.apache.org/POM/4.0.0" xmlns:xsi="http://www.w3.org/2001/XMLSchema-instance"
xsi:schemaLocation="http://maven.apache.org/POM/4.0.0 http://maven.apache.org/xsd/maven-4.0.0.xsd">
<modelVersion>4.0.0</modelVersion>
<groupId>org.example</groupId>
<artifactId>studyDom4j</artifactId>
<version>1.0-SNAPSHOT</version>
<name>studyDom4j</name>
<!-- FIXME change it to the project's website -->
<url>http://www.example.com</url>
<properties>
<project.build.sourceEncoding>UTF-8</project.build.sourceEncoding>
<maven.compiler.source>1.7</maven.compiler.source>
<maven.compiler.target>1.7</maven.compiler.target>
</properties>
<dependencies>
<!-- https://mvnrepository.com/artifact/ch.qos.logback/logback-classic -->
<dependency>
<groupId>org.slf4j</groupId>
<artifactId>slf4j-api</artifactId>
<version>1.7.7</version>
</dependency>
<dependency>
<groupId>ch.qos.logback</groupId>
<artifactId>logback-core</artifactId>
<version>1.1.7</version>
</dependency>
<dependency>
<groupId>ch.qos.logback</groupId>
<artifactId>logback-access</artifactId>
<version>1.1.7</version>
</dependency>
<dependency>
<groupId>ch.qos.logback</groupId>
<artifactId>logback-classic</artifactId>
<version>1.1.7</version>
</dependency>
<dependency>
<groupId>junit</groupId>
<artifactId>junit</artifactId>
<version>4.11</version>
<scope>test</scope>
</dependency>
<!-- https://mvnrepository.com/artifact/dom4j/dom4j -->
<dependency>
<groupId>dom4j</groupId>
<artifactId>dom4j</artifactId>
<version>1.6.1</version>
</dependency>
</dependencies>
<build>
<pluginManagement><!-- lock down plugins versions to avoid using Maven defaults (may be moved to parent pom) -->
<plugins>
<!-- clean lifecycle, see https://maven.apache.org/ref/current/maven-core/lifecycles.html#clean_Lifecycle -->
<plugin>
<artifactId>maven-clean-plugin</artifactId>
<version>3.1.0</version>
</plugin>
<!-- default lifecycle, jar packaging: see https://maven.apache.org/ref/current/maven-core/default-bindings.html#Plugin_bindings_for_jar_packaging -->
<plugin>
<artifactId>maven-resources-plugin</artifactId>
<version>3.0.2</version>
</plugin>
<plugin>
<artifactId>maven-compiler-plugin</artifactId>
<version>3.8.0</version>
</plugin>
<plugin>
<artifactId>maven-surefire-plugin</artifactId>
<version>2.22.1</version>
</plugin>
<plugin>
<artifactId>maven-jar-plugin</artifactId>
<version>3.0.2</version>
</plugin>
<plugin>
<artifactId>maven-install-plugin</artifactId>
<version>2.5.2</version>
</plugin>
<plugin>
<artifactId>maven-deploy-plugin</artifactId>
<version>2.8.2</version>
</plugin>
<!-- site lifecycle, see https://maven.apache.org/ref/current/maven-core/lifecycles.html#site_Lifecycle -->
<plugin>
<artifactId>maven-site-plugin</artifactId>
<version>3.7.1</version>
</plugin>
<plugin>
<artifactId>maven-project-info-reports-plugin</artifactId>
<version>3.0.0</version>
</plugin>
</plugins>
</pluginManagement>
</build>
</project>
這裏還用了日誌工具 sfl4j + logback
<!-- 級別從高到低 OFF 、 FATAL 、 ERROR 、 WARN 、 INFO 、 DEBUG 、 TRACE 、 ALL -->
<!-- 日誌輸出規則 根據當前ROOT 級別,日誌輸出時,級別高於root默認的級別時 會輸出 -->
<!-- 以下 每個配置的 filter 是過濾掉輸出文件裏面,會出現高級別文件,依然出現低級別的日誌信息,通過filter 過濾只記錄本級別的日誌 -->
<!-- scan 當此屬性設置爲true時,配置文件如果發生改變,將會被重新加載,默認值爲true。 -->
<!-- scanPeriod 設置監測配置文件是否有修改的時間間隔,如果沒有給出時間單位,默認單位是毫秒。當scan爲true時,此屬性生效。默認的時間間隔爲1分鐘。 -->
<!-- debug 當此屬性設置爲true時,將打印出logback內部日誌信息,實時查看logback運行狀態。默認值爲false。 -->
<configuration scan="true" scanPeriod="60 seconds" debug="false">
<!-- 動態日誌級別 -->
<jmxConfigurator />
<!-- 定義日誌文件 輸出位置 -->
<!-- <property name="log_dir" value="C:/test" />-->
<property name="log_dir" value="./log" />
<!-- 日誌最大的歷史 30天 -->
<property name="maxHistory" value="30" />
<!-- ConsoleAppender 控制檯輸出日誌 -->
<appender name="console" class="ch.qos.logback.core.ConsoleAppender">
<encoder>
<pattern>
<!-- 設置日誌輸出格式 -->
%d{yyyy-MM-dd HH:mm:ss.SSS} %-5level %logger - %msg%n
</pattern>
</encoder>
</appender>
<!-- ERROR級別日誌 -->
<!-- 滾動記錄文件,先將日誌記錄到指定文件,當符合某個條件時,將日誌記錄到其他文件 RollingFileAppender -->
<appender name="ERROR" class="ch.qos.logback.core.rolling.RollingFileAppender">
<!-- 過濾器,只記錄WARN級別的日誌 -->
<!-- 果日誌級別等於配置級別,過濾器會根據onMath 和 onMismatch接收或拒絕日誌。 -->
<filter class="ch.qos.logback.classic.filter.LevelFilter">
<!-- 設置過濾級別 -->
<level>ERROR</level>
<!-- 用於配置符合過濾條件的操作 -->
<onMatch>ACCEPT</onMatch>
<!-- 用於配置不符合過濾條件的操作 -->
<onMismatch>DENY</onMismatch>
</filter>
<!-- 最常用的滾動策略,它根據時間來制定滾動策略.既負責滾動也負責出發滾動 -->
<rollingPolicy class="ch.qos.logback.core.rolling.TimeBasedRollingPolicy">
<!--日誌輸出位置 可相對、和絕對路徑 -->
<fileNamePattern>
${log_dir}/error/%d{yyyy-MM-dd}/error-log.log
</fileNamePattern>
<!-- 可選節點,控制保留的歸檔文件的最大數量,超出數量就刪除舊文件假設設置每個月滾動,且<maxHistory>是6, 則只保存最近6個月的文件,刪除之前的舊文件。注意,刪除舊文件是,那些爲了歸檔而創建的目錄也會被刪除 -->
<maxHistory>${maxHistory}</maxHistory>
</rollingPolicy>
<encoder>
<pattern>
<!-- 設置日誌輸出格式 -->
%d{yyyy-MM-dd HH:mm:ss.SSS} %-5level %logger - %msg%n
</pattern>
</encoder>
</appender>
<!-- WARN級別日誌 appender -->
<appender name="WARN" class="ch.qos.logback.core.rolling.RollingFileAppender">
<!-- 過濾器,只記錄WARN級別的日誌 -->
<!-- 果日誌級別等於配置級別,過濾器會根據onMath 和 onMismatch接收或拒絕日誌。 -->
<filter class="ch.qos.logback.classic.filter.LevelFilter">
<!-- 設置過濾級別 -->
<level>WARN</level>
<!-- 用於配置符合過濾條件的操作 -->
<onMatch>ACCEPT</onMatch>
<!-- 用於配置不符合過濾條件的操作 -->
<onMismatch>DENY</onMismatch>
</filter>
<rollingPolicy class="ch.qos.logback.core.rolling.TimeBasedRollingPolicy">
<!--日誌輸出位置 可相對、和絕對路徑 -->
<fileNamePattern>${log_dir}/warn/%d{yyyy-MM-dd}/warn-log.log</fileNamePattern>
<maxHistory>${maxHistory}</maxHistory>
</rollingPolicy>
<encoder>
<pattern>%d{yyyy-MM-dd HH:mm:ss.SSS} %-5level %logger - %msg%n</pattern>
</encoder>
</appender>
<!-- INFO級別日誌 appender -->
<appender name="INFO" class="ch.qos.logback.core.rolling.RollingFileAppender">
<filter class="ch.qos.logback.classic.filter.LevelFilter">
<level>INFO</level>
<onMatch>ACCEPT</onMatch>
<onMismatch>DENY</onMismatch>
</filter>
<rollingPolicy class="ch.qos.logback.core.rolling.TimeBasedRollingPolicy">
<fileNamePattern>${log_dir}/info/%d{yyyy-MM-dd}/info-log.log</fileNamePattern>
<maxHistory>${maxHistory}</maxHistory>
</rollingPolicy>
<encoder>
<pattern>%d{yyyy-MM-dd HH:mm:ss.SSS} %-5level %logger - %msg%n</pattern>
</encoder>
</appender>
<!-- DEBUG級別日誌 appender -->
<appender name="DEBUG" class="ch.qos.logback.core.rolling.RollingFileAppender">
<filter class="ch.qos.logback.classic.filter.LevelFilter">
<level>DEBUG</level>
<onMatch>ACCEPT</onMatch>
<onMismatch>DENY</onMismatch>
</filter>
<rollingPolicy class="ch.qos.logback.core.rolling.TimeBasedRollingPolicy">
<fileNamePattern>${log_dir}/debug/%d{yyyy-MM-dd}/debug-log.log</fileNamePattern>
<maxHistory>${maxHistory}</maxHistory>
</rollingPolicy>
<encoder>
<pattern>%d{yyyy-MM-dd HH:mm:ss.SSS} %-5level %logger - %msg%n</pattern>
</encoder>
</appender>
<!-- TRACE級別日誌 appender -->
<appender name="TRACE" class="ch.qos.logback.core.rolling.RollingFileAppender">
<filter class="ch.qos.logback.classic.filter.LevelFilter">
<level>TRACE</level>
<onMatch>ACCEPT</onMatch>
<onMismatch>DENY</onMismatch>
</filter>
<rollingPolicy class="ch.qos.logback.core.rolling.TimeBasedRollingPolicy">
<fileNamePattern>${log_dir}/trace/%d{yyyy-MM-dd}/trace-log.log</fileNamePattern>
<maxHistory>${maxHistory}</maxHistory>
</rollingPolicy>
<encoder>
<pattern>%d{yyyy-MM-dd HH:mm:ss.SSS} %-5level %logger - %msg%n</pattern>
</encoder>
</appender>
<!-- root級別 DEBUG -->
<root>
<!-- 打印debug級別日誌及以上級別日誌 -->
<level value="debug" />
<!-- 控制檯輸出 -->
<appender-ref ref="console" />
<!-- 文件輸出 -->
<appender-ref ref="ERROR" />
<appender-ref ref="INFO" />
<appender-ref ref="WARN" />
<appender-ref ref="DEBUG" />
<appender-ref ref="TRACE" />
</root>
</configuration>
然後就可以開啓 dom4j 玩轉 xml 大法了。
使用 InputStream 從本地讀 xml 文件進行解析
package org.example;
import org.dom4j.Document;
import org.dom4j.DocumentException;
import org.dom4j.io.SAXReader;
import org.slf4j.Logger;
import org.slf4j.LoggerFactory;
import java.io.File;
import java.io.FileInputStream;
import java.io.FileNotFoundException;
import java.io.InputStream;
/**
* Hello world!
*
*/
public class App
{
private static Logger logger = LoggerFactory.getLogger(App.class);
public static void main( String[] args )
{
System.out.println( "Hello World!" );
try {
useInputStreamOperaXML();
}catch (FileNotFoundException | DocumentException e){
e.printStackTrace();
}
}
/**
* 使用 InputStream 從本地讀 xml 文件進行解析
*/
private static void useInputStreamOperaXML() throws FileNotFoundException, DocumentException {
logger.info("使用 InputStream 從本地讀 xml 文件進行解析 start");
SAXReader reader = new SAXReader();
File file = new File("book.xml");
if(file.exists()){
InputStream in = new FileInputStream(file);
Document document = reader.read(file);
logger.info(document.asXML());
}
logger.info("使用 InputStream 從本地讀 xml 文件進行解析 end");
}
}
輸出
2020-04-14 21:39:05.491 INFO org.example.App - 使用 InputStream 從本地讀 xml 文件進行解析 start
2020-04-14 21:39:05.586 INFO org.example.App - <?xml version="1.0" encoding="UTF-8"?>
<books>
<books id="book1" date="2020">
<author>騰訊</author>
<category>產品</category>
</books>
<books id="book1" date="2020">
<author>阿里</author>
<category>運營</category>
</books>
<books id="book1" date="2020">
<author>華爲</author>
<category>技術</category>
</books>
</books>
2020-04-14 21:39:05.587 INFO org.example.App - 使用 InputStream 從本地讀 xml 文件進行解析 end
通過DocumentHelper創建(解析)一個Document對象,併爲Document添加元素
/**
* 通過DocumentHelper創建(解析)一個Document對象,併爲Document添加元素
*/
private static void useDocumentCreateXML() {
logger.info("----------- org.example.App.useDocumentCreateXML start");
Document document = DocumentHelper.createDocument();
Element root = document.addElement("root");
Element p1 =root.addElement("person")
.addAttribute("age", "18")
.addText("張三");
Element p2 =root.addElement("person")
.addAttribute("age", "19")
.addText("李四");
Element p3 =root.addElement("person")
.addAttribute("age", "20")
.addText("王五");
logger.info(document.asXML());
logger.info("----------- org.example.App.useDocumentCreateXML end");
}
輸出
2020-04-14 21:51:06.405 INFO org.example.App - ----------- org.example.App.useDocumentCreateXML start
2020-04-14 21:51:06.406 INFO org.example.App - <?xml version="1.0" encoding="UTF-8"?>
<root><person age="18">張三</person><person age="19">李四</person><person age="20">王五</person></root>
2020-04-14 21:51:06.406 INFO org.example.App - ----------- org.example.App.useDocumentCreateXML end
解析XML字符串獲取Document對象 public static Document parseText(String text) throws DocumentException {…}
private static void useDocumentParseText() throws DocumentException {
logger.info("----------- org.example.App.useDocumentParseText start");
Document document = DocumentHelper.parseText("<?xml version=\"1.0\" encoding=\"UTF-8\"?>\n" +
"<root><person age=\"18\">張三</person><person age=\"19\">李四</person><person age=\"20\">王五</person></root>");
logger.info(document.asXML());
logger.info("----------- org.example.App.useDocumentParseText end");
}
輸出
2020-04-14 22:06:04.718 INFO org.example.App - ----------- org.example.App.useDocumentParseText start
2020-04-14 22:06:04.759 INFO org.example.App - <?xml version="1.0" encoding="UTF-8"?>
<root><person age="18">張三</person><person age="19">李四</person><person age="20">王五</person></root>
2020-04-14 22:06:04.759 INFO org.example.App - ----------- org.example.App.useDocumentParseText end
模擬SpringIOC 依賴注入機制(通過反射實現),有如下spring_core.xml配置,主要使用了反射機制
首先在項目當前目錄中創建 spring-ioc.xml 文件模擬
<?xml version="1.0" encoding="UTF-8"?>
<beans>
<bean id="testBean" class="com.just.Test"/>
</beans>
// 模擬SpringIOC 依賴注入機制(通過反射實現),有如下spring_core.xml配置,主要使用了反射機制
private static void simulateIOC() throws FileNotFoundException, DocumentException, ClassNotFoundException, NoSuchMethodException, InvocationTargetException, IllegalAccessException, InstantiationException {
logger.info("----------- org.example.App.simulateIOC start");
SAXReader reader = new SAXReader();
// File file =new File("logback.xml");
File file = new File("spring-ioc.xml");
if(file.exists()){
InputStream in = new FileInputStream(file);
Document document = reader.read(in);
logger.info(document.asXML());
Element root = document.getRootElement();
Element foo;
for (Iterator i = root.elementIterator("bean"); i.hasNext();){
foo = (Element) i.next();
//針對每一個bean實例獲取id和name屬性
Attribute id = foo.attribute("id");
Attribute clazz = foo.attribute("class");
//利用反射,通過class名稱獲取class對象
Class bean = Class.forName(clazz.getText());
Object object = bean.newInstance();
Method method = bean.getMethod("sayHello");
Object result = method.invoke(object);
logger.info(result.toString());
// other 省略無關的反射操作
}
logger.info("----------- org.example.App.simulateIOC end");
}
}
輸出
2020-04-14 22:55:43.869 INFO org.example.App - ----------- org.example.App.simulateIOC start
2020-04-14 22:55:43.919 INFO org.example.App - <?xml version="1.0" encoding="UTF-8"?>
<beans>
<bean id="testBean" class="org.example.HelloWorld"/>
</beans>
2020-04-14 22:55:43.921 INFO org.example.App - hello
2020-04-14 22:55:43.923 INFO org.example.App - ----------- org.example.App.simulateIOC end
將Document寫出
// 將 document對象 輸出爲xml文件
private static void outPutDocumentXML() throws Exception {
logger.info("----------- org.example.App.outPutDocumentXML start");
String xmlStr = "<books>"
+ "<book><title>AAA</title><author>aaa</author></book>"
+ "<book><title>BBB</title><author>bbb</author></book>"
+ "<book><title>CCC</title><author>ccc</author></book>"
+ "</books>";
// 解析字符串獲取document對象
Document document = DocumentHelper.parseText(xmlStr);
//設置輸出樣式(整潔)
OutputFormat format = OutputFormat.createPrettyPrint();
// 將document寫出到output.xml中,並指定輸出樣式
XMLWriter writer = new XMLWriter(new FileOutputStream("output.xml"),format);
writer.write(document);
// 使用pretty(整潔)樣式輸出到控制檯
writer = new XMLWriter(System.out, format);
writer.write(document);
System.out.println("--------------------------------------------------------------");
// 使用緊湊樣式輸出到控制檯
format = OutputFormat.createCompactFormat();
writer = new XMLWriter(System.out, format);
writer.write(document);
logger.info("----------- org.example.App.outPutDocumentXML end");
}
輸出
2020-04-14 22:59:59.308 INFO org.example.App - ----------- org.example.App.outPutDocumentXML start
<?xml version="1.0" encoding="UTF-8"?>
<books>
<book>
<title>AAA</title>
<author>aaa</author>
</book>
<book>
<title>BBB</title>
<author>bbb</author>
</book>
<book>
<title>CCC</title>
<author>ccc</author>
</book>
</books>
--------------------------------------------------------------
<?xml version="1.0" encoding="UTF-8"?>
<books><book><title>AAA</title><author>aaa</author></book><book><title>BBB</title><author>bbb</author></book><book><title>CCC</title><author>ccc</author></book></books>2020-04-14 22:59:59.350 INFO org.example.App - ----------- org.example.App.outPutDocumentXML end
源碼地址: https://github.com/weijieqiu/iStudy/tree/master/studyDom4j/studyDom4j