Apache Camel 没有可用的类型转换器

Question

我用 camel 定义了一个处理器，它允许我生成一个带有计时器的 jaxb java bean，并将 pojo 写入 xml 文件。但是当我启动应用程序时出现以下错误：

08:09:00 警告 [or.ap.ca.co.ti.TimerConsumer]（Camel（camel-1）线程 #2 - timer://generateInvoice）处理交换时出错。交换 [20E715FDB7EFE19-0000000000000000]。由以下原因引起：[java.io.IOException - org.apache.camel.NoTypeConversionAvailableException：没有类型转换器可用于从类型：java.util.LinkedList 转换为所需类型：java.io.InputStream，值为 [com.mycompany.model.Invoice@21e27bf , com.mycompany.model.Invoice@1fd7b4bf, com.mycompany.model.Invoice@9cb7bae, com.mycompany.model.Invoice@2751bc51 ...

我的代码如下：

from("timer:generateInvoice?period={{xml.timer.period}}&delay={{xml.timer.delay}}")
        .log("Generating randomized invoice XML data")
        .process("invoiceGenerator")
        .marshal(jaxbDataFormat)
        .to("file:{{xml.location}}");

我的发电机轰鸣：

@Override
    public void process(Exchange exchange) throws Exception {

        Random random = new Random();
        List<Invoice> invoices = new LinkedList<>();

        for (int i = 0; i < 100; i++) {

            String invoiceNumber = String.format("invoice-%d", random.nextInt());

            Invoice invoice = new Invoice();
            invoice.setInvoiceNumber(invoiceNumber);
            invoice.setAmount(random.nextDouble());

            Instant now = Instant.now();

            GregorianCalendar cal1 = new GregorianCalendar();
            cal1.setTimeInMillis(now.toEpochMilli());
            invoice.setInsertionDate(DatatypeFactory.newInstance().newXMLGregorianCalendar());
            invoice.setInvoiceType(INVOICE_TYPE[random.nextInt(INVOICE_TYPE.length)]);
            invoices.add(invoice);
        }
        exchange.getMessage().setBody(invoices);
    }

我已经尝试实现 java.util.LinkedList 到所需类型的转换器：java.io.InputStream

与：

@Converter
    public InputStream ListToInputStream(List<Invoice> invoices) throws IOException {

            ByteArrayOutputStream baos = new ByteArrayOutputStream();
            ByteArrayInputStream bios = null;
            try {

                ObjectFactory objFactory = new ObjectFactory();

                JAXBContext jaxbContext = JAXBContext.newInstance("com.webinage.model");
                Marshaller marshaller = jaxbContext.createMarshaller();
                marshaller.setProperty(Marshaller.JAXB_FORMATTED_OUTPUT, Boolean.TRUE);

                for(Invoice invoice : invoices) {
                    marshaller.marshal(invoice, baos);
                }
                bios = new ByteArrayInputStream(new byte[baos.size()]);
                bios.read(baos.toByteArray());
            } catch (Exception e) {
                e.printStackTrace();
            } finally {
                baos.close();
            }
            return bios;
    }

但是同样的异常出现了... 请问你有什么想法吗？

Answer 1

很可能 List 不是您要放入 Exchange 的内容。我假设您希望输出 XML 类似于：

<Invoices>
 <Invoice>...</Invoice>
 <Invoice>...</Invoice>
 ...
</Invoices>

在这种情况下，声明容器可能是最直接的 class:

@XmlRootElement
public class Invoices {
  private List<Invoice> invoices;
}

（省略getter和setter）。

然后生成您的架构并将此 Invoices 对象放入 Exchange。

Apache Camel 没有可用的类型转换器

Apache Camel No type converter available

java

apache-camel

quarkus