Convert XML to JSON in Java

XML can represent attributes, mixed text, namespaces, repeated elements, and ordering in ways JSON cannot represent directly. Pick a library and a stable mapping convention, then test it with real documents.

Quick Start#

The following example uses the standard Java API or a widely used package for this task.

Using Jackson XML#

1// Dependency: com.fasterxml.jackson.dataformat:jackson-dataformat-xml2XmlMapper xmlMapper = new XmlMapper();3ObjectMapper jsonMapper = new ObjectMapper();45JsonNode tree = xmlMapper.readTree(xml);6String json = jsonMapper.writerWithDefaultPrettyPrinter()7    .writeValueAsString(tree);8System.out.println(json);

Common Operations#

This second pattern covers a common production operation or a safer way to handle real input.

Bind to a model when structure matters#

1User user = xmlMapper.readValue(xml, User.class);2String json = jsonMapper.writeValueAsString(user);

Important Notes#

Tree conversion is convenient for generic documents, but a typed model gives you more control when namespaces, attributes, and collection wrappers are part of a stable contract.

Best Practices#

1. Treat external input as untrusted and handle parse/validation errors explicitly.
2. Keep encoding, units, formats, and library-specific mapping rules explicit at system boundaries.
3. Add test vectors that cover empty input, Unicode text, malformed input, and representative production data.

References#

• W3C XML
• RFC 8259: JSON
• Java API Documentation