Java - lesson 6 | HackIndia Skills

Java - lesson 6 | HackIndia Skills | HackIndia

[
  {
    "id": 1,
    "name": "Asha Nair",
    "city": "Kochi",
    "skills": ["Java", "SQL", "Git"],
    "expectedSalaryLpa": 6.0
  },
  {
    "id": 2,
    "name": "Rohit Sharma",
    "city": "Pune",
    "skills": ["Java", "Spring", "PostgreSQL"],
    "expectedSalaryLpa": 8.5
  }
]

Example

Read a JSON file

This method reads the full file into a String. Your JSON parser can use that string later.

It also gives a clear error if the file is missing, which is better than a long stack trace during a demo.

import java.io.IOException;
import java.nio.file.Files;
import java.nio.file.Path;

public class JsonFileReader {
    public static String readJson(String filePath) {
        Path path = Path.of(filePath);

        if (!Files.exists(path)) {
            throw new IllegalArgumentException("File not found: " + filePath);
        }

        try {
            return Files.readString(path);
        } catch (IOException e) {
            throw new RuntimeException("Could not read file: " + filePath, e);
        }
    }
}

// Usage:
// String json = JsonFileReader.readJson("data/candidates.json");

Files and JSON handling

One rule

Why JSON here

Sample data file

Reading files safely

Read a JSON file

Avoid hard-coded data

Check AI output

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