标签:xmlns enc put 开始时间 app xsd dem bsp override
最近工作中遇到了解析xml文件问题,xpath < SAX < spring-oxm,
遂记录下来
代码结构:
取得所指定节点
1 package com.example.demo.sax.common; 2 3 import java.util.ArrayList; 4 import java.util.List; 5 6 import com.example.demo.sax.model.User; 7 import lombok.Builder; 8 import org.xml.sax.Attributes; 9 import org.xml.sax.SAXException; 10 import org.xml.sax.helpers.DefaultHandler; 11 12 public class XmlParseHandler extends DefaultHandler { 13 // xml片段内容 14 private StringBuilder sb = new StringBuilder(); 15 // 片段名称 16 private String strTag = ""; 17 // 开始时间 18 long starTime; 19 // 结束时间 20 long endTime; 21 // 开始记录 22 private boolean bolStartRecordFlg = false; 23 24 public XmlParseHandler(String tag) { 25 this.strTag = tag; 26 } 27 28 /** 29 * 文档解析开始调用 30 */ 31 @Override 32 public void startDocument() throws SAXException { 33 starTime = System.currentTimeMillis(); 34 System.out.println("开始读取文档:" + starTime); 35 } 36 37 /** 38 * 文档解析结束后调用 39 */ 40 @Override 41 public void endDocument() throws SAXException { 42 endTime = System.currentTimeMillis(); 43 System.out.println("结束读取文档:" + endTime); 44 System.out.println("用时:" + (endTime - starTime)); 45 } 46 47 48 @Override 49 public void startElement(String uri, String localName, String qName, Attributes attributes) throws SAXException { 50 51 if (qName.equals(strTag)) { 52 bolStartRecordFlg = true; 53 } 54 if (bolStartRecordFlg) { 55 sb.append("<" + qName + ">"); 56 } 57 58 } 59 60 @Override 61 public void endElement(String uri, String localName, String qName) throws SAXException { 62 63 if (bolStartRecordFlg) { 64 sb.append("</" + qName + ">"); 65 } 66 if (qName.equals(strTag)) { 67 bolStartRecordFlg = false; 68 //System.out.println(sb.toString()); 69 doSomething(sb.toString()); 70 sb.delete(0,sb.length()); 71 } 72 } 73 74 @Override 75 public void characters(char[] ch, int start, int length) throws SAXException { 76 if(bolStartRecordFlg){ 77 sb.append(new String(ch,start,length)); 78 } 79 } 80 81 public void doSomething(String strXml){ 82 83 } 84 }
考虑替换
package com.example.demo.sax.handler; import com.example.demo.sax.common.XmlParseHandler; import java.util.ArrayList; public class Handler extends XmlParseHandler { private ArrayList<String> arrayList ; public Handler(ArrayList<String> arrayList, String tag) { super(tag); this.arrayList = arrayList; } @Override public void doSomething(String strXml) { arrayList.add(strXml); } }
测试代码
package com.example.demo.sax; import com.example.demo.sax.handler.Handler; import org.springframework.context.annotation.Configuration; import org.springframework.stereotype.Component; import javax.xml.parsers.SAXParser; import javax.xml.parsers.SAXParserFactory; import java.util.ArrayList; @Configuration public class TestSAX { private static String file= "D:\\WorkSpace\\sax\\src\\main\\resources\\xml\\users.xml"; public static void main(String[] args) throws Exception{ ArrayList<String> arrayList = new ArrayList<String>(); SAXParserFactory factory = SAXParserFactory.newInstance(); SAXParser parser = factory.newSAXParser(); parser.parse(file,new Handler(arrayList,"user")); arrayList.toString(); } }
这是将来会用到的依赖,先引入进来。
<?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>com.example.demo</groupId> <artifactId>sax</artifactId> <version>0.0.1-SNAPSHOT</version> <packaging>jar</packaging> <name>sax</name> <description>Demo project for Spring Boot</description> <parent> <groupId>org.springframework.boot</groupId> <artifactId>spring-boot-starter-parent</artifactId> <version>2.0.3.RELEASE</version> <relativePath/> <!-- lookup parent from repository --> </parent> <properties> <project.build.sourceEncoding>UTF-8</project.build.sourceEncoding> <project.reporting.outputEncoding>UTF-8</project.reporting.outputEncoding> <java.version>1.8</java.version> </properties> <dependencies> <dependency> <groupId>org.springframework.boot</groupId> <artifactId>spring-boot-starter</artifactId> </dependency> <dependency> <groupId>org.projectlombok</groupId> <artifactId>lombok</artifactId> <optional>true</optional> </dependency> <dependency> <groupId>org.springframework</groupId> <artifactId>spring-oxm</artifactId> <version>3.0.5.RELEASE</version> </dependency> <dependency> <groupId>org.springframework.boot</groupId> <artifactId>spring-boot-starter-test</artifactId> <scope>test</scope> </dependency> </dependencies> <build> <plugins> <plugin> <groupId>org.springframework.boot</groupId> <artifactId>spring-boot-maven-plugin</artifactId> </plugin> </plugins> </build> </project>
经过测试遍历300mb的xml文件,仅仅需要4秒,真的快。。。。。。
标签:xmlns enc put 开始时间 app xsd dem bsp override
原文地址:https://www.cnblogs.com/hanshaowu/p/9277671.html