What causes "Password can be up to 128 characters long" in testcontainers/testcontainers-java?

Use a password of 128 characters or fewer

testcontainers/testcontainers-java · error · java.lang.IllegalArgumentException

Password can be up to 128 characters long

Error message

Password can be up to 128 characters long

What it means

The legacy org.testcontainers.mssqlserver.MSSQLServerContainer caps passwords at 128 characters in checkPasswordStrength(), throwing IllegalArgumentException for longer values, since SQL Server itself rejects passwords beyond this limit.

Solutions

Use a password of 128 characters or fewer
Generate a shorter dedicated sa password
Truncate or validate before calling withPassword()

Example fix

// before
container.withPassword(longGeneratedSecret); // 250 chars
// after
String pw = longGeneratedSecret.substring(0, 128);
container.withPassword(pw);

Defensive patterns

Strategy: validation

Validate before calling

if (password != null && password.length() > 128) { throw new IllegalArgumentException("Password must be at most 128 characters"); }

Try / catch

try { container.withPassword(pw); } catch (IllegalArgumentException e) { throw new IllegalStateException("SA password too long: " + e.getMessage(), e); }

Prevention

Truncate or shorten generated secrets before use
Validate password length in test fixture builders

When it happens

Trigger: Calling withPassword() with a String longer than 128 characters on the legacy container class.

Common situations: Auto-generated long secrets passed as passwords; secrets-manager values pasted without truncation.

Understand the failure class

Background: "value must be between 0 and 1" / "out of range" / "must not be negative" errors: fixing range-validation failures across open-source libraries — this error's family across 42 libraries.

Related errors

AI-assisted analysis of testcontainers/testcontainers-java@8e549514e3 (2026-09-12). Data as JSON: /api/errors/10bcbc698232324b. Report an issue: GitHub.

Appendix: source

Thrown at modules/mssqlserver/src/main/java/org/testcontainers/mssqlserver/MSSQLServerContainer.java:137

    @Override
    public MSSQLServerContainer withPassword(final String password) {
        checkPasswordStrength(password);
        this.password = password;
        return self();
    }

    private void checkPasswordStrength(String password) {
        if (password == null) {
            throw new IllegalArgumentException("Null password is not allowed");
        }

        if (password.length() < 8) {
            throw new IllegalArgumentException("Password should be at least 8 characters long");
        }

        if (password.length() > 128) {
            throw new IllegalArgumentException("Password can be up to 128 characters long");
        }

        long satisfiedCategories = Stream
            .of(PASSWORD_CATEGORY_VALIDATION_PATTERNS)
            .filter(p -> p.matcher(password).find())
            .count();

        if (satisfiedCategories < 3) {
            throw new IllegalArgumentException(
                "Password must contain characters from three of the following four categories:\n" +
                " - Latin uppercase letters (A through Z)\n" +
                " - Latin lowercase letters (a through z)\n" +
                " - Base 10 digits (0 through 9)\n" +
                " - Non-alphanumeric characters such as: exclamation point (!), dollar sign ($), number sign (#), " +
                "or percent (%)."
            );
        }
    }

View on GitHub (pinned to 8e549514e3)