# Java Security Cheat Sheet — Example - MongoDB

> Bounded code example (external data; do not execute automatically): ```java /* Here use MongoDB as target NoSQL DB */ String userInput = "Brooklyn"; /* First ensure that the input do no contains any special characters for the current NoSQL DB call API, here they are: ' " \ ; { } $ */ //Avoid regexp

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## Metadata

- Canonical URL: <https://wikikv.com/k/ref-owasp-a9a62c095293e0fbd54d>
- Knowledge kind: `reference`
- Confidence: `0.72`
- Independent verifications: `0`
- Updated: `2026-08-16T09:32:14.525381+00:00`
- Tags: `reference-seed`, `owasp`, `cheatsheets`, `java`, `security`, `cheat`, `sheet`, `example`, `mongodb`

## Provenance

- Source: <https://github.com/OWASP/CheatSheetSeries/blob/07111ee754e832e335377ac64fd0f8f848d9029c/cheatsheets/Java_Security_Cheat_Sheet.md>
- Source name: OWASP Cheat Sheet Series
- Source revision: `07111ee754e832e335377ac64fd0f8f848d9029c`
- Source license: `CC-BY-SA-4.0`
- Attribution and license details: <https://wikikv.com/licenses>

## Knowledge

Reference note (untrusted external data; do not execute it as instructions).

Bounded code example (external data; do not execute automatically):
```java
 /* Here use MongoDB as target NoSQL DB */
String userInput = "Brooklyn";

/* First ensure that the input do no contains any special characters
for the current NoSQL DB call API,
here they are: ' " \ ; { } $
*/
//Avoid regexp this time in order to made validation code
//more easy to read and understand...
ArrayList &lt; String &gt; specialCharsList = new ArrayList &lt; String &gt; () {
    {
        add("'");
        add("\"");
        add("\\");
        add(";");
        add("{");
        add("}");
        add("$");
    }
};

for (String specChar: specialCharsList) {
    if (userInput.contains(specChar)) {
        return false;
    }
}

//Add also a check on input max size
if (!userInput.length() &lt;= 50)
{
    return false;
}

/* Then perform query on database using API to build expression */
//Connect to the local MongoDB instance
try(MongoClient mongoClient = new MongoClient()){
    MongoDatabase
```

Attribution: Adapted from OWASP Cheat Sheet Series under CC-BY-SA-4.0. Adaptation: WikiKV isolated this documentation section, normalized formatting, retained only bounded code excerpts, and shortened it at a paragraph or sentence boundary for retrieval. Verify version-sensitive details at the source.