使用 Apache Camel 从另一个 API 使用 JSON 并将其写入 CSV

Question

我是 apache 骆驼的新手。我想从另一个 api 的端点 url (http://localhost:8080/employeePayload) 使用 json 数据。我想使用这个 json 数据，使用 apache camel 将其解组到 POJO 并将其写入 CSV 文件。在我用 CSV 编写它之前，我需要为每个属性/列添加分隔符 |"。 此外，我必须将标题和尾部记录添加到 CSV 文件中。标头由一些静态列名和一些运行时名称组成。标题列数将与 json 数据不同。 Header 有 15 列，json 有 110 列）。

有没有办法在不使用 setter 方法的情况下将 json/pojo 绑定到 CSV 文件（因为我有 110 个属性，不能全部使用 setter）？

有人可以建议实现这一目标的最佳方法吗？

如果标题部分不清楚，请告诉我如何使用分隔符(|") 将 json 写入 CSV。

编辑：我可以从另一个 API 使用 json。但是，我不确定如何使用 apache camel 或任何其他库在不使用 getter 和 setter 的情况下使用分隔符将其写入 CSV。

Answer 1

我找到了答案。 随着开发的进展，我有很多问题，我已经将它们发布在 stackoverflow 中。

我决定总结一下我发现的一切。

请参考以下帖子。 Unable to add header and footer to the file using Apache Camel Bindy

这个解决方案解决了我在各个阶段遇到的许多问题。

问题 1) 使用 BindyFixedLengthDataFormat 为平面文件添加了动态页眉和页脚。顾名思义，它是固定长度的。在生成正文后，我必须指定最大长度并修剪空格。 （我仍然可能需要考虑使用不同的类，因为我不希望长度固定）。 BindyCsvDataFormat 没有向文件添加动态页眉和页脚的选项。

问题 2) 我需要用 |" 替换管道分隔符。

问题 3）我没有使用 jetty 公开将被硬编码的端点 url，而是使用了 rest 配置，这样主机名将不再被硬编码，您可以部署到任何环境。

@Component
    public class EmployeePackageRoute extends RouteBuilder {
    
        @Autowired
        private Header header;
        
        private Trailer footer;
        
        private String file_name;
        
        @SuppressWarnings("deprecation")
        @Override
        public final void configure() {
            
            System.out.println("fetching employee details from employee api");
            
            final SimpleDateFormat TARGET_DATE_FORMAT = new SimpleDateFormat("YYYYMMDDHHMMSS");
            String date = TARGET_DATE_FORMAT.format(new Date());
            
            String year = date.substring(0, 8);
            String hr = date.substring(9, 13);
    
            try {
                restConfiguration().component("jetty").port(8000).bindingMode(RestBindingMode.json);
                rest("/api/test/getTestResponse")
                .get().consumes(MediaType.APPLICATION_JSON_VALUE).route().setBody().constant("return test response");
                
                rest("/api/bcr/recurringPaymentsDeduct")
                .post().consumes(MediaType.APPLICATION_JSON_VALUE).type(RecurringPaymentResults.class).outType(ResponseEntity.class).route()
                .process(
                        ex -> {
                            
                            RecurringPaymentResults result = ex.getIn().getBody(RecurringPaymentResults.class);
                            List<RecurringPaymentsDeduct> employee = result.getResults();
                            file_name = Constants.FILE_NUMBER_DEV+"_"+date+"_"+Constants.AUMBCR_HRMD+result.getSequenceNumber()+"_"+Constants.DUT8G2I+".SAP";
                            header.setHeader7(Constants.FILE_NUMBER_DEV+"_"+date+"_"+Constants.AUMBCR_HRMD+result.getSequenceNumber()+"_"+Constants.DUT8G2I+".SAP");
                            
                            header.setHeader8(year);
                            header.setHeader9(hr);
                            header.setHeader10(Constants.ENVIRONMENT);
                            
                            footer = new Footer("Footer",(employee.size()+2));
                            
                            ex.getOut().setBody(employee);
                        })
                .to("seda:recurringPaymentsFeed");
                
                final DataFormat recurringPaymentsBindy = new BindyFixedLengthDataFormat(RecurringPaymentsDeduct.class);
                
                from("seda:recurringPaymentsFeed")
                .startupOrder(2)
                .log("add footer to the file")
                .process(
                        ex -> {
                            
                            Map<String, Object> headerObjMap = new HashMap<String,Object>();
                            headerObjMap.put(Header.class.getName(), header);
                            System.out.println(" *** file_name 1 - "+file_name);
                            Map<String, Object> footerObjMap = new HashMap<String,Object>();
                            footerObjMap.put(Footer.class.getName(), footer);
                            
                            ex.getOut().setHeader(BindyFixedLengthDataFormat.CAMEL_BINDY_FIXED_LENGTH_HEADER, headerObjMap);
                            ex.getOut().setBody(ex.getIn().getBody());
                            ex.getOut().setHeader(BindyFixedLengthDataFormat.CAMEL_BINDY_FIXED_LENGTH_FOOTER, footerObjMap);
                            
                        })
                .marshal(recurringPaymentsBindy)
                .convertBodyTo(byte[].class, "iso-8859-1")
                .setBody(body().regexReplaceAll("\\|", "\\|\""))
                .log("csv processed")
                .to("file://app/bcr-files?fileName=recurringPaymentsDeduct.SAP")
                .end();
                
                
            } catch(Exception e) {
                System.out.println("Error occurred while processing employee data: "+e.getMessage());
                e.printStackTrace();
            }
        }
        
    }

@Data
@Section(number = 2)
@FixedLengthRecord(header = Header.class, footer = Trailer.class)
public class RecurringPaymentsDeduct implements Serializable {

    private static final long serialVersionUID = 1L;
    
    @DataField(pos = 1, length = 10, delimiter = "|", trim = true)
    public String RECTY;
    
    @DataField(pos = 2, length = 10, delimiter = "|", trim = true)
    public String CLIID;
    
    @DataField(pos = 3, length = 10, delimiter = "|", trim = true)
    public String INTCA;
    
    @DataField(pos = 4, length = 10, delimiter = "|", trim = true)
    public String ORDNO;
    
    @DataField(pos = 5, length = 10, delimiter = "|", trim = true)
    public String IOPER;
    
    @DataField(pos = 6, length = 10, delimiter = "|", trim = true)
    public String INFTY;
    
    @DataField(pos = 7, length = 10, delimiter = "|", trim = true)
    public String SUBTY;
    
    @DataField(pos = 8, length = 10, delimiter = "|", trim = true)
    public String BEGDA;
    
    @DataField(pos = 9, length = 10, delimiter = "|", trim = true)
    public String ENDDA;
    
    @DataField(pos = 10, length = 10, trim = true)
    public String OBJPS;
        
}

@Configuration
@EnableConfigurationProperties
@ConfigurationProperties("adp")
@Data
@Section(number = 1)
@FixedLengthRecord()
public class Header implements Serializable {

    private static final long serialVersionUID = 1L;

    @DataField(pos = 1, length = 5, delimiter = "|", trim = true)
    private String header1;
    
    @DataField(pos = 2, length = 5, delimiter = "|", trim = true)
    private String header2;
    
    @DataField(pos = 3, length = 15, delimiter = "|", trim = true)
    private String header3;
    
    @DataField(pos = 4, length = 60, delimiter = "|", trim = true)
    private String header4;
    
    @DataField(pos = 5, length = 15, delimiter = "|", trim = true)
    private String header5;
    
    @DataField(pos = 6, length = 30, delimiter = "|", trim = true)
    private String header6;
    
    @DataField(pos = 7, length = 30, delimiter = "|", trim = true)
    private String header7;
    
    @DataField(pos = 8, length =  8, pattern = "YYYYMMDD", delimiter = "|", trim = true)
    private String header8;
    
    @DataField(pos = 9, length = 6, delimiter = "|", trim = true)
    private String header9;
    
    @DataField(pos = 10, length = 1, delimiter = "|", trim = true)
    private String header10;
    
    @DataField(pos = 11, length = 2, delimiter = "|", trim = true)
    private String header11;
    
    @DataField(pos = 12, length = 10, delimiter = "|", trim = true)
    private String header12;
    
    @DataField(pos = 13, length = 10, delimiter = "|", trim = true)
    private String header13;
    
    @DataField(pos = 14, length = 10, align = "L", trim = true)
    private String header14;
}

@Data
@Section(number = 3)
@FixedLengthRecord()
public class Footer implements Serializable {

    private static final long serialVersionUID = 1L;

    @DataField(pos = 1, length = 7, delimiter = "|", trim = true)
    private String trailer;
    
    @DataField(pos = 2, length = 5, align = "L", trim = true)
    private int count;
    
    public Footer() {
        
    }
    
    public Footer(String trailer, int count) {
        this.trailer = trailer;
        this.count = count;
    }
}