JAXB解析xml

古城微笑少年丶 2022-05-27 13:40 211阅读 0赞

JAXB解析xml真是非常的方便，只需在对象上加上注解，标注对应xml文件的节点即可。很方便。下面是一个示例。

封装解析用到的代码，提供三个方法，一个是将字符串解析为对象，一个是读取一个xml文件解析，另一个是将输入流解析为对象。

package cn.com.servyou.hs.support.core.util;
    import lombok.extern.slf4j.Slf4j;
    import javax.xml.bind.JAXBContext;
    import javax.xml.bind.JAXBException;
    import javax.xml.bind.Unmarshaller;
    import java.io.ByteArrayInputStream;
    import java.io.InputStream;
    import java.io.UnsupportedEncodingException;
    
    /** * @author susq * @since 2018-04-13-20:54 */
    @Slf4j
    public class XmlUtils { 
    
        @SuppressWarnings("unchecked")
        public static <T> T parseInputStream(Class<T> clazz, InputStream dataStream) throws JAXBException { 
            try { 
                JAXBContext jc = JAXBContext.newInstance(clazz);
                Unmarshaller u = jc.createUnmarshaller();
                return (T) u.unmarshal(dataStream);
            } catch (JAXBException e) { 
                 log.error(e.getMessage());
            }
            return null;
        }
    
        @SuppressWarnings("unchecked")
        public static <T> T parseInputString(Class<T> clazz, String dataStr) throws JAXBException, UnsupportedEncodingException { 
            try { 
                JAXBContext jc = JAXBContext.newInstance(clazz);
                Unmarshaller u = jc.createUnmarshaller();
                return (T) u.unmarshal(new ByteArrayInputStream(dataStr.getBytes("UTF-8")));
            } catch (JAXBException e) { 
                log.error(e.getMessage());
            }
            return null;
        }
      
      @SuppressWarnings("unchecked")
        public static <T> T parseFile(Class<T> clazz, String fileName) throws JAXBException { 
            try { 
                JAXBContext jc = JAXBContext.newInstance(clazz);
                Unmarshaller u = jc.createUnmarshaller();
                return (T) u.unmarshal(new File(fileName));
            } catch (JAXBException e) { 
                log.error(e.getMessage());
                throw e;
            }
        }
    
    	/** * 对象转换成xmlString */
        public static String convertToXmlStr(Object obj) throws Exception { 
            //创建输出流
            StringWriter sw = new StringWriter();
            sw.append("<?xml version=\"1.0\" encoding=\"UTF-8\"?>" + "\n");
            JAXBContext context = JAXBContext.newInstance(obj.getClass());
            Marshaller marshaller = context.createMarshaller();
            marshaller.setProperty(Marshaller.JAXB_FORMATTED_OUTPUT, Boolean.TRUE);
            marshaller.setProperty(Marshaller.JAXB_FRAGMENT, Boolean.TRUE);
            marshaller.marshal(obj, sw);
            return sw.toString();
        }
    
        /** * 对象转换成xmlString, * 会带上 xsi:noNamespaceSchemaLocation="request.xsd" xmlns:xsi="http://www.w3.org/2001/XMLSchema-instance" */
        public static String convertToXmlStrWithXsi(Object obj, String schemaLocation) throws Exception { 
            StringWriter sw = new StringWriter();
            sw.append("<?xml version=\"1.0\" encoding=\"UTF-8\"?>" + "\n");
            JAXBContext context = JAXBContext.newInstance(obj.getClass());
            Marshaller marshaller = context.createMarshaller();
            marshaller.setProperty(Marshaller.JAXB_FORMATTED_OUTPUT, Boolean.TRUE);
            marshaller.setProperty(Marshaller.JAXB_FRAGMENT, Boolean.TRUE);
            marshaller.setProperty(Marshaller.JAXB_NO_NAMESPACE_SCHEMA_LOCATION, schemaLocation);
            marshaller.marshal(obj, sw);
            return sw.toString();
        }
    }

对象加上注解即可，注意根节点要单独标注@XmlRootElement，其他节点都是@XmlElement 标注即可。

package com.susq.zipBase64;
    
    import javax.xml.bind.annotation.XmlAccessType;
    import javax.xml.bind.annotation.XmlAccessorType;
    import javax.xml.bind.annotation.XmlElement;
    import javax.xml.bind.annotation.XmlRootElement;
    import java.math.BigDecimal;
    import java.util.Date;
    
    /** * @author susq * @since 2018-04-17-10:23 */
    @XmlRootElement(name = "fpmx")
    @XmlAccessorType(XmlAccessType.FIELD)
    public class UnAuthInvoiceDto { 
        @XmlElement(name = "fpLb")
        private Integer fplb;
        @XmlElement(name = "fpdm")
        private String fpdm;
        @XmlElement(name = "fphm")
        private String fphm;
        @XmlElement(name = "kprq")
        private Date kprq;
        @XmlElement(name = "xfsbh")
        private String sfsbh;
        @XmlElement(name = "xfmc")
        private String xfmc;
        @XmlElement(name = "gfsbh")
        private String gfsbh;
        @XmlElement(name = "gfmc")
        private String gfmc;
        @XmlElement(name = "je")
        private BigDecimal je;
        @XmlElement(name = "se")
        private BigDecimal se;
        @XmlElement(name = "")
        private String skm;
        @XmlElement(name = "jqbh")
        private String jqbh;
        @XmlElement(name = "sklx")
        private Integer sklx;
    
        // getter setter toString 省略
    }

测试

public static void main(String[] args) throws JAXBException { 
            String xml = "<fpmx>\n" +
                    " <fpLb>1</fpLb>\n" +
                    " <fpdm>120</fpdm>\n" +
                    " <fphm>07868</fphm>\n" +
                    " <kprq>2018-03-30 16:35:09.0</kprq>\n" +
                    " <xfsbh>91C</xfsbh>\n" +
                    " <xfmc>有限公司</xfmc>\n" +
                    " <gfsbh>91397067</gfsbh>\n" +
                    " <gfmc>有限公司</gfmc>\n" +
                    " <je>689513.07</je>\n" +
                    " <se>117217.23</se>\n" +
                    " <skm><9;9>1&-<215+4</skm>\n" +
                    " <jqbh>66152799</jqbh>\n" +
                    " <sklx>1</sklx>\n" +
                    " </fpmx>";
    
            UnAuthInvoiceDto dto = parseInputString(UnAuthInvoiceDto.class, xml);
            System.out.println(dto.toString());
        }

输出：

UnAuthInvoiceDto{fplb=1, fpdm='1230', fphm='078', kprq=null, sfsbh='9112011', xfmc='）有限公司', gfsbh='914401165602397067', gfmc='品有限公司', je=689513.07, se=117217.23, skm='<9-9804-89036+*4<67/1*0>2988<//375>9>1>*0+--247*357971593<*/6*->78--<215+4', jqbh='66199', sklx=1}

即使是复杂的嵌套对象，也可以解析。例如：根节点下面是个列表，创建对应结构的对象，一个上层对象包含了下层对象的列表。只需要将更节点移到对应位置即可。

@XmlRootElement(name = "fpmxs") 
    @XmlAccessorType(XmlAccessType.FIELD)
    public class UnAuthInvoiceResult { 
    
        @XmlElement(name = "fpmx")
        private List<UnAuthInvoiceDto> unAuthInvoiceDtoList;
    
    	// getter setter 省略
    }

测试

public static void main(String[] args) throws JAXBException { 
            String xml = "<fpmxs>\n" +
                    " <fpmx>\n" +
                    " <fpLb>1</fpLb>\n" +
                    " <fpdm>1130</fpdm>\n" +
                    " <fphm>0768</fphm>\n" +
                    " <kprq>2018-03-30 16:35:09.0</kprq>\n" +
                    " <xfsbh>91126325C</xfsbh>\n" +
                    " <xfmc>有限公司</xfmc>\n" +
                    " <gfsbh>91497067</gfsbh>\n" +
                    " <gfmc>制品有限公司</gfmc>\n" +
                    " <je>689513.07</je>\n" +
                    " <se>117217.23</se>\n" +
                    " <skm>->78--<215+4</skm>\n" +
                    " <jqbh>661799</jqbh>\n" +
                    " <sklx>1</sklx>\n" +
                    " </fpmx>\n" +
                    " <fpmx>\n" +
                    " <fpLb>1</fpLb>\n" +
                    " <fpdm>2130</fpdm>\n" +
                    " <fphm>0183</fphm>\n" +
                    " <kprq>2018-03-14 00:00:00.0</kprq>\n" +
                    " <xfsbh>912199</xfsbh>\n" +
                    " <xfmc>限公司</xfmc>\n" +
                    " <gfsbh>967</gfsbh>\n" +
                    " <gfmc>限公司</gfmc>\n" +
                    " <je>22244.82</je>\n" +
                    " <se>3781.62</se>\n" +
                    " <skm>8-t;-4&g>717+/67-</skm>\n" +
                    " <jqbh/>\n" +
                    " <sklx>1</sklx>\n" +
                    " </fpmx>" +
                    " </fpmxs>";
    
            UnAuthInvoiceResult dto = parseInputString(UnAuthInvoiceResult.class, xml);
            System.out.println(dto.toString());
        }

输出：

UnAuthInvoiceResult{unAuthInvoiceDtoList=[UnAuthInvoiceDto{fplb=1, fpdm='120130', fphm='0788', kprq=null, sfsbh='9116325C', xfmc='神有限公司', gfsbh='9197067', gfmc='品有限公司', je=689513.07, se=117217.23, skm='<9-9lt;*/6*-1;78--<215+4', jqbh='66199', sklx=1}, UnAuthInvoiceDto{fplb=1, fpdm='210010', fphm='013683', kprq=null, sfsbh='91', xfmc='限公司', gfsbh='92397067', gfmc='品有限公司', je=22244.82, se=3781.62, skm='8-/73*501-75>>-4-', jqbh='', sklx=1}]}

### 可能遇到的问题 ###

MalformedByteSequenceException: 3 字节的 UTF-8 序列的字节 2 无效

MalformedByteSequenceException: 2 字节的 UTF-8 序列的字节 2 无效

中文乱码

这些都是编码方式的问题。通过byte\[\] 创建字符串，如 String s = new String(b, “UTF-8”)，通过字符串.getByte()取得字节数组再创建输入流的时候，如：new ByteArrayInputStream(xml.getBytes(“UTF-8”))

都需要指定编码方式。