文章列表

• • • 讀記錄跨多行文件
    • • 1、讀跨多行文件job配置
      • 2、讀跨多行文件reader
      • 3、自定義FieldSetMapper
      • 4、讀跨多行文件processor
      • 5、讀跨多行文件writer

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前言：在工作中可能會(huì)遇到SpringBatch讀取的文件記錄跨多行或者文件中存在多種不同的記錄格式，不必?fù)?dān)心SpringBatch已經(jīng)幫我們把接口都預(yù)留好了，只需要稍微改造就可以輕松實(shí)現(xiàn)。

讀記錄跨多行文件

當(dāng)Flat文件格式非標(biāo)準(zhǔn)是，通過實(shí)現(xiàn)記錄分隔策略接口RecordSeparatorPolicy來實(shí)現(xiàn)非標(biāo)準(zhǔn)Flat格式文件。非標(biāo)準(zhǔn)Flat文件有多種情況，例如記錄跨多行、以特定的字符開頭、以特定的字符結(jié)尾。

下面講的例子是每?jī)尚斜硎疽粭l記錄：

412222,201,tom,2020-02-27 ,china 412453,203,tqm,2020-03-27 ,us 412222,205,tym,2020-05-27 ,jap

默認(rèn)的記錄分割策略SimpleRecordSeparatorPolicy或者DefaultRecordSeparatorPolicy已經(jīng)不能處理此類文件。我們可以實(shí)現(xiàn)接口RecordSeparatorPolicy來自定義分割策略MulitiLineRecordSeparatorPolicy

讀記錄跨多行文件時(shí)，使用到的核心組件類圖如下：

在本類圖中除了MulitiLineRecordSeparatorPolicy和CommonFieldSetMapper是自定義實(shí)現(xiàn)的，其他組件都是SpringBatch自帶。

MulitiLineRecordSeparatorPolicy：負(fù)責(zé)從文件中確認(rèn)一條完整記錄，在本實(shí)現(xiàn)中每讀到四個(gè)逗號(hào)分隔符，則認(rèn)為是一條完整的記錄

/*** @author shuliangzhao* @date 2020/12/6 13:05*/ public class MulitiLineRecordSeparatorPolicy implements RecordSeparatorPolicy {private String delimiter = ",";private int count = 0;public int getCount() {return count;}public void setCount(int count) {this.count = count;}public String getDelimiter() {return delimiter;}public void setDelimiter(String delimiter) {this.delimiter = delimiter;}@Overridepublic boolean isEndOfRecord(String record) {return countDelimiter(record) == count;}private int countDelimiter(String record) {String temp = record;int index = -1;int count = 0;while ((index=temp.indexOf(",")) != -1) {temp = temp.substring(index +1);count++;}return count;}@Overridepublic String postProcess(String record) {return record;}@Overridepublic String preProcess(String record) {return record;} }

delimiter ：定義為讀的的分割符號(hào)
count：分隔符總數(shù)，給定的字符串包含的分隔符個(gè)數(shù)等于此值，則認(rèn)為是一條完整的記錄。

1、讀跨多行文件job配置

讀跨多行文件job基于javabean配置如下

/*** 讀記錄跨多行文件* @author shuliangzhao* @date 2020/12/6 13:38*/ @Configuration @EnableBatchProcessing public class MulitiLineConfiguration {@Autowiredprivate JobBuilderFactory jobBuilderFactory;@Autowiredprivate StepBuilderFactory stepBuilderFactory;@Autowiredprivate PartitonMultiFileProcessor partitonMultiFileProcessor;@Autowiredprivate PartitionMultiFileWriter partitionMultiFileWriter;@Beanpublic Job mulitiLineJob() {return jobBuilderFactory.get("mulitiLineJob").start(mulitiLineStep()).build();}@Beanpublic Step mulitiLineStep() {return stepBuilderFactory.get("mulitiLineStep").<CreditBill,CreditBill>chunk(12).reader(mulitiLineRecordReader()).processor(partitonMultiFileProcessor).writer(partitionMultiFileWriter).build();}@Bean@StepScopepublic MulitiLineRecordReader mulitiLineRecordReader() {return new MulitiLineRecordReader(CreditBill.class);} }

2、讀跨多行文件reader

MulitiLineRecordReader詳細(xì)如下

/*** @author shuliangzhao* @date 2020/12/6 13:09*/ public class MulitiLineRecordReader extends FlatFileItemReader {public MulitiLineRecordReader(Class clz) {setResource(CommonUtil.createResource("D:\\aplus\\muliti\\muliti.csv"));String[] names = CommonUtil.names(clz);DefaultLineMapper defaultLineMapper = new DefaultLineMapper();CommonFieldSetMapper commonFieldSetMapper = new CommonFieldSetMapper();commonFieldSetMapper.setTargetType(clz);defaultLineMapper.setFieldSetMapper(commonFieldSetMapper);DelimitedLineTokenizer delimitedLineTokenizer = new DelimitedLineTokenizer();delimitedLineTokenizer.setFieldSetFactory(new DefaultFieldSetFactory());delimitedLineTokenizer.setNames(names);delimitedLineTokenizer.setDelimiter(",");defaultLineMapper.setLineTokenizer(delimitedLineTokenizer);MulitiLineRecordSeparatorPolicy mulitiLineRecordSeparatorPolicy = new MulitiLineRecordSeparatorPolicy();mulitiLineRecordSeparatorPolicy.setCount(4);mulitiLineRecordSeparatorPolicy.setDelimiter(",");setRecordSeparatorPolicy(mulitiLineRecordSeparatorPolicy);setLineMapper(defaultLineMapper);} }

3、自定義FieldSetMapper

自定義CommonFieldSetMapper

*** @author shuliangzhao* @date 2020/12/4 22:14*/ public class CommonFieldSetMapper<T> implements FieldSetMapper<T> {private Class<? extends T> type;@Overridepublic T mapFieldSet(FieldSet fieldSet) throws BindException {try {T t = type.newInstance();Field[] declaredFields = type.getDeclaredFields();if (declaredFields != null) {for (Field field : declaredFields) {field.setAccessible(true);if (field.getName().equals("id")) {continue;}String name = field.getType().getName();if (name.equals("java.lang.Integer")) {field.set(t,fieldSet.readInt(field.getName()));}else if (name.equals("java.lang.String")) {field.set(t,fieldSet.readString(field.getName()));}else if (name.equals("java.util.Date")) {field.set(t,fieldSet.readDate(field.getName()));}else{field.set(t,fieldSet.readString(field.getName()));}}return t;}} catch (Exception e) {e.printStackTrace();}return null;}public void setTargetType(Class<? extends T> type) {this.type = type;}

4、讀跨多行文件processor

PartitonMultiFileProcessor 詳細(xì)如下

@Component @StepScope public class PartitonMultiFileProcessor implements ItemProcessor<CreditBill,CreditBill> {@Overridepublic CreditBill process(CreditBill item) throws Exception {CreditBill creditBill = new CreditBill();creditBill.setAcctid(item.getAcctid());creditBill.setAddress(item.getAddress());creditBill.setAmout(item.getAmout());creditBill.setDate(item.getDate());creditBill.setName(item.getName());return creditBill;} }

5、讀跨多行文件writer

PartitionMultiFileWriter詳細(xì)如下

@Component @StepScope public class PartitionMultiFileWriter implements ItemWriter<CreditBill> {@Autowiredprivate CreditBillMapper creditBillMapper;@Overridepublic void write(List<? extends CreditBill> items) throws Exception {if (items != null && items.size() > 0) {items.stream().forEach(item -> {creditBillMapper.insert(item);});}} }

至此，我們完成了對(duì)跨行讀文件的處理。
如果想更詳細(xì)查看以上所有代碼請(qǐng)移步到github：讀跨多行文件詳細(xì)代碼

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