难以将 Google Guava 映射元素添加到 java 中的数组

Question

您好，我需要将 Google Multimap class 中的几个元素添加到数组，以便能够将它们传递给 JAXB 编组方法进行编组。

public void marshall(Multimap<String, Product> supplierProducts) throws JAXBException {
        JAXBContext context = JAXBContext.newInstance(Product.class);
        Marshaller marshaller = context.createMarshaller();
        marshaller.setProperty(Marshaller.JAXB_FORMATTED_OUTPUT, Boolean.TRUE);
        Product[] panasonic = new Product[10];
        Product[] apple = new Product[10];
        Product[] sony = new Product[10];

        for (Product product : supplierProducts.values()) {
        if (product.getSupplier().equals("Panasonic")) {

        } else if (product.getSupplier().equals("Apple")) {
            apple
        } else {
            sony
        }
        }
        marshaller.marshal(panasonic, new File("src/output/panasonic.xml"));
        marshaller.marshal(apple, new File("src/output/apple.xml"));
        marshaller.marshal(sony, new File("src/output/sony.xml"));

    }

在地图中我有 Product objects.The key 是 3 values:panasonic,sony 或 apple 之一，而 values 是一个产品，有几个 fields.I 需要添加到每个数组仅包含特定密钥的产品，以便我可以将每个供应商的产品写入 3 个单独的 xml 文件。所以问题是我不知道该怎么做 this.It 真的很困惑 fast.Any 非常感谢帮助！

Answer 1

您可以使用以下方法解决问题，版本 2：

public void marshallV1(Multimap<String, Product> supplierProducts) throws JAXBException {
        JAXBContext context = JAXBContext.newInstance(Product.class);
        Marshaller marshaller = context.createMarshaller();
        marshaller.setProperty(Marshaller.JAXB_FORMATTED_OUTPUT, Boolean.TRUE);
        List<Product> panasonic = new ArrayList<>();
        List<Product> apple = new ArrayList<>();
        List<Product> sony = new ArrayList<>();

        for (Product product : supplierProducts.values()) {
        if (product.getSupplier().equals("Panasonic")) {
           panasonic.add(product ); 
        } else if (product.getSupplier().equals("Apple")) {
            apple.add(product ); 
        } else {
            sony.add(product ); 
        }
        }
        marshaller.marshal(panasonic, new File("src/output/panasonic.xml"));
        marshaller.marshal(apple, new File("src/output/apple.xml"));
        marshaller.marshal(sony, new File("src/output/sony.xml"));

    }

版本 2：

public void marshallV2(Multimap<String, List<Product>> supplierProducts) throws JAXBException {
            JAXBContext context = JAXBContext.newInstance(Product.class);
            Marshaller marshaller = context.createMarshaller();
            marshaller.setProperty(Marshaller.JAXB_FORMATTED_OUTPUT, Boolean.TRUE);
            List<Product> panasonic = supplierProducts.get("panasonic ");
            List<Product> apple = supplierProducts.get("apple ");
            List<Product> sony = supplierProducts.get("sony ");
    
  
            marshaller.marshal(panasonic, new File("src/output/panasonic.xml"));
            marshaller.marshal(apple, new File("src/output/apple.xml"));
            marshaller.marshal(sony, new File("src/output/sony.xml"));
    
        }

难以将 Google Guava 映射元素添加到 java 中的数组

Difficulty adding Google Guava map elements to array in java

java

xml

arrays

jaxb

guava