Create and clean up a temporary file.
Java: Create a unique file and remove it in finally even when the operation fails.
import java.util.*;
import java.util.stream.*;
import java.util.regex.*;
import java.nio.file.*;
import java.nio.charset.StandardCharsets;
import java.time.*;
import java.time.format.DateTimeFormatter;
import java.time.temporal.*;
import java.math.*;
import java.io.*;
import java.net.*;
import java.security.MessageDigest;
import java.util.concurrent.*;
public class Main {
public static void main(String[] args) throws Exception {
Path file = Files.createTempFile("example-", ".txt");
try {
Files.writeString(file, "temporary");
System.out.println(Files.readString(file));
} finally {
Files.deleteIfExists(file);
}
System.out.println(Files.exists(file));
}
}
Expected output EXAMPLE
temporary false
Details
Save as Main.java, compile with javac Main.java, and run java Main. Uses the Java 21 standard library. Create a unique file and remove it in finally even when the operation fails.
Tested on Ubuntu 24.04.5 LTS · · openjdk 21.0.12.1 2026-08-18 · openjdk-21-jdk-headless 21.0.12.1+1-1~24.04.4
Test inputs, results and environment
The exact published code ran in a dedicated Linux test container with prepared inputs. Unprivileged snippet process, external networking disabled, read-only root filesystem, and a fresh temporary working directory. Fixtures and output records are isolated from the application database. Testing covers this example and its stated checks, not every input, operating system, or runtime version. The Linux container shares its host's kernel; this is not a native Windows test.
- Architecture / host kernel
- x86_64 / 6.18.54.1-microsoft-standard-WSL2
- Snippet identity / locale
- uid=65534, gid=65534 (unprivileged) / C.UTF-8
- Interpreter invocation
javac Main.java && java Main- Container image ID
sha256:32dc2d998158b6554c99b73b533f423696a0f3e31e8cbea9db10b5eee9a2fadd- Code SHA-256
17b5ad4597b0a5583f92dfeb2ceb24df2ac0b7564877251768109abc501bcd98- Dependencies
- openjdk-21-jdk-headless 21.0.12.1+1-1~24.04.4
Test input setup
These are the prepared inputs used by the test harness. See Details above for the prerequisites and how to run this example.
# No input files required.
Observed standard output
temporary false
Exit code: 0. Standard error: empty. Validation: Exact stdout comparison. System-dependent values above are one recorded run.