Replit api

JSON Parsing Error in API Response

API returns unexpected response format causing JSON parsing errors. The response doesn't match expected structure.

Missing fields, unexpected types, or null values break deserialization.

Error Messages You Might See

com.fasterxml.jackson.databind.exc.UnrecognizedPropertyException com.google.gson.JsonSyntaxException Failed to parse JSON response
com.fasterxml.jackson.databind.exc.UnrecognizedPropertyExceptioncom.google.gson.JsonSyntaxExceptionFailed to parse JSON response

Common Causes

  1. Response format changed by API provider
  2. Jackson/Gson expecting different field structure
  3. Null values in required fields
  4. Field name mismatch (camelCase vs snake_case)
  5. API returns HTML error page instead of JSON

How to Fix It

For Spring Boot/Jackson, use @JsonProperty for field mapping and @JsonInclude(Include.NON_NULL) for nulls. Enable lenient parsing. Add @JsonAnySetter for flexible responses. Log raw response before parsing to inspect actual content. Use API documentation or Swagger to verify response schema.

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Frequently Asked Questions

How do I map snake_case API fields to camelCase?

Use @JsonProperty("snake_case_field") on Java field

How do I handle optional API fields?

Use @JsonInclude(Include.NON_NULL) and make field Optional or null-safe

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