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Module import declarations

Import all exported packages of a module with a single declaration.

Modules

Code Comparison

✕ Java 8

import java.util.List;
import java.util.Map;
import java.util.stream.Collectors;
import java.io.IOException;
import java.nio.file.Files;
import java.nio.file.Path;

✓ Java 25+

import module java.base;

// All of java.util, java.io, java.nio
// etc. available in one line

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Why the modern way wins

🧹

One line

Replace a wall of imports with a single module import.

📦

Module-aware

Leverages the module system to import coherent sets of packages.

🚀

Quick starts

Perfect for scripts and prototypes where import lists are tedious.

Old Approach

Many Imports

Modern Approach

import module

Since JDK

Difficulty

Intermediate

JDK Support

Module import declarations

Available

Finalized in JDK 25 LTS (JEP 511, Sept 2025).

How it works

Module import declarations let you import everything a module exports with one line. This is especially useful for java.base which covers collections, I/O, streams, and more.

Type inference with var

Java 8

Map<String, List<Integer>> map =
    new HashMap<String, List<Integer>>();
for (Map.Entry<String, List<Integer>> e
    : map.entrySet()) {
    // verbose type noise
}

Java 10+

var map = new HashMap<String, List<Integer>>();
for (var entry : map.entrySet()) {
    // clean and readable
}

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Language Beginner

Text blocks for multiline strings

Java 8

String json = "{\n" +
    "  \"name\": \"Duke\",\n" +
    "  \"age\": 30\n" +
    "}";

Java 15+

String json = """
    {
      "name": "Duke",
      "age": 30
    }""";

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JDK 15+ →

Language Beginner

Switch expressions

Java 8

String msg;
switch (day) {
    case MONDAY:
        msg = "Start";
        break;
    case FRIDAY:
        msg = "End";
        break;
    default:
        msg = "Mid";
}

Java 14+

String msg = switch (day) {
    case MONDAY  -> "Start";
    case FRIDAY  -> "End";
    default      -> "Mid";
};

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JDK 14+ →