google/gson · error · IllegalArgumentException

Invalid version

Error message

Invalid version: ${version}

What it means

Thrown by GsonBuilder.setVersion(double) when the supplied version is NaN or negative. Versions drive field/class inclusion via @Since and @Until annotations, so a non-finite or negative number is meaningless and rejected with an IllegalArgumentException before being applied to the Excluder.

Solutions

1. Pass a non-negative, finite double version (>= 0.0 and not NaN), e.g. setVersion(1.2).
2. Validate the value before calling: if (!Double.isNaN(v) && v >= 0.0) builder.setVersion(v).
3. Use 0.0 or omit setVersion to disable versioning rather than passing a sentinel.
4. Parse config with Double.parseDouble guarded by a try/catch to avoid NaN propagation.

Example fix

// before
builder.setVersion(parseDoubleOrNaN(config)); // NaN -> throws

// after
double v = parseDoubleOrNaN(config);
if (!Double.isNaN(v) && v >= 0.0) builder.setVersion(v);

// Validate version before applying
if (Double.isNaN(version) || version < 0.0) {
  throw new IllegalArgumentException("version must be >= 0 and not NaN, got " + version);
}
builder.setVersion(version);

try { builder.setVersion(v); }
catch (IllegalArgumentException e) {
  if (e.getMessage().startsWith("Invalid version")) { /* default version or fail config */ }
  else throw e;
}

When it happens

Trigger: Passing Double.NaN; a negative double (e.g. from a subtraction bug); computing the version from unparsed config that yields NaN; passing 0.0/0.0.

Common situations: Reading version from a properties file and parsing fails to NaN; arithmetic that can go negative; default/uninitialized double field passed through; test values like -1 to mean 'unset'.

Related errors

• Invalid style
• Class does not implement any supported type adapter class…
• Only combinations of \n and \r are allowed in newline.
• Only combinations of spaces and tabs are allowed in indent.
• The date pattern ' ' is not valid

AI-assisted analysis of google/gson@310ac341f2 (2026-08-10). Data as JSON: /api/errors/da1e36742bce9038. Report an issue: GitHub.

Appendix: source

Thrown at gson/src/main/java/com/google/gson/GsonBuilder.java:207

  /**
   * Configures Gson to enable versioning support. Versioning support works based on the annotation
   * types {@link Since} and {@link Until}. It allows including or excluding fields and classes
   * based on the specified version. See the documentation of these annotation types for more
   * information.
   *
   * <p>By default versioning support is disabled and usage of {@code @Since} and {@code @Until} has
   * no effect.
   *
   * @param version the version number to use.
   * @return a reference to this {@code GsonBuilder} object to fulfill the "Builder" pattern
   * @throws IllegalArgumentException if the version number is NaN or negative
   * @see Since
   * @see Until
   */
  @CanIgnoreReturnValue
  public GsonBuilder setVersion(double version) {
    if (Double.isNaN(version) || version < 0.0) {
      throw new IllegalArgumentException("Invalid version: " + version);
    }
    excluder = excluder.withVersion(version);
    return this;
  }

  /**
   * Configures Gson to excludes all class fields that have the specified modifiers. By default,
   * Gson will exclude all fields marked {@code transient} or {@code static}. This method will
   * override that behavior.
   *
   * <p>This is a convenience method which behaves as if an {@link ExclusionStrategy} which excludes
   * these fields was {@linkplain #setExclusionStrategies(ExclusionStrategy...) registered with this
   * builder}.
   *
   * @param modifiers the field modifiers. You must use the modifiers specified in the {@link
   *     java.lang.reflect.Modifier} class. For example, {@link
   *     java.lang.reflect.Modifier#TRANSIENT}, {@link java.lang.reflect.Modifier#STATIC}.
   * @return a reference to this {@code GsonBuilder} object to fulfill the "Builder" pattern

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