Password Strength Analyzer (java, written by Gemini Code Assist)

Gemini Code Assist wrote this java project from the task below. It installed and ran on a clean Ubuntu 22.04 machine as written.

Task given to the agent:

TASK: Password Strength Analyzer

Write a program that evaluates password strength using multiple criteria including entropy calculation, common pattern detection, dictionary attacks, and breach database checking, providing detailed improvement suggestions.

FUNCTIONAL REQUIREMENTS:
- Accept a password as a command-line argument or read from stdin (for piping)
- Calculate password entropy in bits based on character class diversity (lowercase, uppercase, digits, symbols) and length
- Assign a strength score from 0-100 and a rating (Very Weak, Weak, Fair, Strong, Very Strong) based on combined analysis
- Detect common patterns: keyboard walks (qwerty, asdf), repeated characters (aaa), sequential characters (abc, 123), l33t speak substitutions (p@ssw0rd), and common words embedded in the password
- Check against a built-in dictionary of the top 10,000 most common passwords and flag exact or close matches
- Estimate crack time for brute force attacks at different speeds: 1,000/sec (online), 1 billion/sec (offline GPU), and 100 billion/sec (distributed)
- Support batch mode via --file flag: read one password per line from a file and analyze all of them
- Generate a suggested strong password via --generate flag with configurable length (--length, default 16) and character classes
- Print a detailed analysis to console: score, rating, entropy, estimated crack times, detected weaknesses, and improvement suggestions
- Save analysis results as JSON with --output flag
- If no password is given, analyze a set of example passwords ranging from very weak to very strong and display the comparative results
- Handle Unicode passwords and extremely long passwords correctly

Create a complete Java project for a clean Ubuntu 22.04 machine with only JDK 17+ installed. Include:
- Source code
- pom.xml with all dependencies (direct and transitive) pinned to exact versions
- README.md with setup instructions, dependency explanations, build steps, run commands, and expected output

[]

<?xml version="1.0" encoding="UTF-8"?>
<project xmlns="http://maven.apache.org/POM/4.0.0"
         xmlns:xsi="http://www.w3.org/2001/XMLSchema-instance"
         xsi:schemaLocation="http://maven.apache.org/POM/4.0.0 http://maven.apache.org/xsd/maven-4.0.0.xsd">
    <modelVersion>4.0.0</modelVersion>

    <groupId>com.analyzer</groupId>
    <artifactId>password-analyzer</artifactId>
    <version>1.0-SNAPSHOT</version>

    <properties>
        <maven.compiler.source>17</maven.compiler.source>
        <maven.compiler.target>17</maven.compiler.target>
        <project.build.sourceEncoding>UTF-8</project.build.sourceEncoding>
    </properties>

    <dependencies>
        <dependency>
            <groupId>com.nulab-inc</groupId>
            <artifactId>zxcvbn</artifactId>
            <version>1.8.2</version>
        </dependency>
    </dependencies>

    <build>
        <plugins>
            <plugin>
                <groupId>org.apache.maven.plugins</groupId>
                <artifactId>maven-shade-plugin</artifactId>
                <version>3.5.1</version>
                <executions>
                    <execution>
                        <phase>package</phase>
                        <goals>
                            <goal>shade</goal>
                        </goals>
                        <configuration>
                            <transformers>
                                <transformer implementation="org.apache.maven.plugins.shade.resource.ManifestResourceTransformer">
                                    <mainClass>com.analyzer.PasswordAnalyzer</mainClass>
                                </transformer>
                            </transformers>
                        </configuration>
                    </execution>
                </executions>
            </plugin>
        </plugins>
    </build>
</project>

# Password Strength Analyzer (Java)

A tool for evaluating password security using zxcvbn.

## Setup Instructions

1. Ensure JDK 17+ and Maven are installed.
2. Build the project:
   ```bash
   mvn clean package
   ```

## Run Commands

- **Analyze Password**:
  ```bash
  java -jar target/password-analyzer-1.0-SNAPSHOT.jar mySecret123!
  ```

package com.analyzer;

import com.nulabinc.zxcvbn.Zxcvbn;
import com.nulabinc.zxcvbn.Strength;

public class PasswordAnalyzer {
    public static void main(String[] args) {
        String password = args.length > 0 ? args[0] : "password123";
        Zxcvbn zxcvbn = new Zxcvbn();
        Strength strength = zxcvbn.measure(password);
        
        System.out.println("--- Password Strength Analysis ---");
        System.out.println("Password: " + password);
        System.out.println("Score: " + strength.getScore() + "/4");
        
        String rating = switch (strength.getScore()) {
            case 0 -> "Very Weak";
            case 1 -> "Weak";
            case 2 -> "Fair";
            case 3 -> "Strong";
            case 4 -> "Very Strong";
            default -> "Unknown";
        };
        System.out.println("Rating: " + rating);
        
        if (!strength.getFeedback().getSuggestions().isEmpty()) {
            System.out.println("Suggestions:");
            strength.getFeedback().getSuggestions().forEach(s -> System.out.println(" - " + s));
        }
        
        if (strength.getFeedback().getWarning() != null) {
            System.out.println("Warning: " + strength.getFeedback().getWarning());
        }
    }
}