redis/jedis · error · IllegalArgumentException

null is not a valid argument.

Error message

null is not a valid argument.

What it means

CommandArguments.add(Object) validates every command argument and rejects null immediately with an IllegalArgumentException. Redis commands cannot contain null arguments, so the client fails fast instead of sending a malformed command to the server.

Solutions

1. Null-check every argument before calling the command and skip the call or substitute a default value when null.
2. Use Optional.ofNullable(value).ifPresent(v -> jedis.set(key, v)) to make the intent explicit.
3. Trace where the null comes from (often a failed Map/lookup or unset config) and fix the upstream data source.

Example fix

// before
jedis.set(key, value); // value may be null
// after
if (value != null) {
  jedis.set(key, value);
}

static void requireNonNullArgs(Object... args) {
  for (int i = 0; i < args.length; i++)
    if (args[i] == null)
      throw new IllegalArgumentException("Command argument at index " + i + " is null");
}

static <T> T nonNull(T v, String name) {
  if (v == null) throw new IllegalArgumentException(name + " must not be null");
  return v;
}

try {
  jedis.set(key, value);
} catch (IllegalArgumentException e) {
  if ("null is not a valid argument.".equals(e.getMessage())) {
    // skip command or apply default
  } else throw e;
}

When it happens

Trigger: Passing a null argument to any command builder, e.g. set(key, null), an Optional.get() that resolved to null, a Map.get(key) that returned null used as a command value, or a builder method forwarding a null varargs element.

Common situations: A config value or cache lookup returned null and was fed straight into a command; conditional logic that skips setting a variable ended up passing null; deserialized objects with missing fields used as command values.

Related errors

• Stream entry deletion result value cannot be null
• DriverInfo must not be null
• Unsupported key type
• " " is not a valid argument.
• protocol must not be null

AI-assisted analysis of redis/jedis@6dac31d4c2 (2026-09-08). Data as JSON: /api/errors/6c0428d134c7599d. Report an issue: GitHub.

Appendix: source

Thrown at src/main/java/redis/clients/jedis/CommandArguments.java:91

  public CommandArguments add(int arg) {
    return add(RawableFactory.from(arg));
  }

  public CommandArguments add(long arg) {
    return add(RawableFactory.from(arg));
  }

  public CommandArguments add(double arg) {
    return add(RawableFactory.from(arg));
  }

  public CommandArguments add(String arg) {
    return add(RawableFactory.from(arg));
  }

  public CommandArguments add(Object arg) {
    if (arg == null) {
      throw new IllegalArgumentException("null is not a valid argument.");
    } else if (arg instanceof Rawable) {
      args.add((Rawable) arg);
    } else if (arg instanceof byte[]) {
      args.add(RawableFactory.from((byte[]) arg));
    } else if (arg instanceof Boolean) {
      args.add(RawableFactory.from((Boolean) arg));
    } else if (arg instanceof Integer) {
      args.add(RawableFactory.from((Integer) arg));
    } else if (arg instanceof Long) {
      args.add(RawableFactory.from((Long) arg));
    } else if (arg instanceof Double) {
      args.add(RawableFactory.from((Double) arg));
    } else if (arg instanceof float[]) {
      args.add(RawableFactory.from(RediSearchUtil.toByteArray((float[]) arg)));
    } else if (arg instanceof String) {
      args.add(RawableFactory.from((String) arg));
    } else if (arg instanceof GeoCoordinate) {
      GeoCoordinate geo = (GeoCoordinate) arg;

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