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Sync Bridge to Java 25: H6 file labels, README mapping

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Ankur
2026-06-24 14:27:07 +05:30
parent 8471913dbd
commit 4091345b20
8 changed files with 58 additions and 89 deletions
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14
02-structural/bridge/AdvancedRemote.java
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@@ -1,23 +1,19 @@
package bridge;
/**
* Refined Abstraction — extends RemoteControl with extra features.
* This is how you vary the "abstraction" side independently of the
* "implementation" side. Both TV and Radio work with this remote,
* even though they know nothing about it.
* Refined Abstraction — extends RemoteControl with additional capabilities.
*
* The device hierarchy doesn't change at all. TV and Radio
* automatically support mute() and jumpToChannel() because they
* implement Device. Zero new code on the implementation side.
*/
public class AdvancedRemote extends RemoteControl {
public AdvancedRemote(Device device) {
super(device);
}
// Extra feature not in the basic remote
public void mute() {
System.out.println(" Muting " + device.getName());
device.setVolume(0);
}
public void jumpToChannel(int channel) {
System.out.println(" Jumping to channel " + channel);
device.setChannel(channel);

7
02-structural/bridge/Device.java
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@@ -1,9 +1,8 @@
package bridge;
/**
* Implementor interface — the "implementation" side of the bridge.
* This is what the Abstraction delegates its real work to.
* TV, Radio, SmartSpeaker etc. all implement this.
* Implementor — the "implementation" side of the bridge.
* All devices (TV, Radio, SmartSpeaker, etc.) implement this.
* The remote controls only know about this interface, never about specific devices.
*/
public interface Device {
boolean isEnabled();

20
02-structural/bridge/Main.java
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@@ -1,29 +1,14 @@
package bridge;
/**
* Bridge Design Pattern — Runnable Demo
*
* Shows how remotes (abstraction) and devices (implementation)
* can vary independently. 4 combinations from 2+2 classes,
* not 4 hard-coded classes.
*
* Run: javac bridge/*.java && java bridge.Main
* Article: https://ankurm.com/bridge-design-pattern-java/
*/
public class Main {
public static void main(String[] args) {
System.out.println("=== Bridge Design Pattern Demo ===\n");
// Combination 1: Basic Remote + TV
System.out.println("-- Basic Remote controlling TV --");
RemoteControl remote1 = new RemoteControl(new TV());
remote1.togglePower();
remote1.volumeUp();
remote1.channelUp();
System.out.println();
// Combination 2: Advanced Remote + Radio
System.out.println("-- Advanced Remote controlling Radio --");
AdvancedRemote remote2 = new AdvancedRemote(new Radio());
@@ -31,16 +16,13 @@ public class Main {
remote2.volumeUp();
remote2.mute();
remote2.jumpToChannel(91);
System.out.println();
// Combination 3: Advanced Remote + TV (no new classes needed)
// Combination 3: Advanced Remote + TV (no new classes needed!)
System.out.println("-- Advanced Remote controlling TV --");
AdvancedRemote remote3 = new AdvancedRemote(new TV());
remote3.togglePower();
remote3.jumpToChannel(5);
remote3.mute();
System.out.println("\n=== Demo complete ===");
System.out.println("3 different remote+device combinations, 0 new classes needed.");
}

22
02-structural/bridge/README.md
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@@ -10,21 +10,23 @@ Decouples remote controls (Abstraction) from devices (Implementation). A basic r
## How to run
```bash
javac bridge/*.java
java bridge.Main
javac bridge/*.java -d out/bridge
java -cp out/bridge bridge.Main
```
Requires Java 11+.
Requires Java 25.
## Files
## Post Section ↔ File Mapping
| File | Role |
| Post Section | File(s) |
|---|---|
| `Device.java` | Implementor interface |
| `TV.java` / `Radio.java` | Concrete Implementors |
| `RemoteControl.java` | Abstraction (holds Device bridge) |
| `AdvancedRemote.java` | Refined Abstraction |
| `Main.java` | Demo entry point |
| Step 1 — The Implementor Interface | `Device.java` |
| Step 2 — Concrete Implementors (TV and Radio) | `TV.java`, `Radio.java` |
| Step 3 — The Abstraction (RemoteControl) | `RemoteControl.java` |
| Step 4 — Refined Abstraction (AdvancedRemote) | `AdvancedRemote.java` |
| Wiring It Together: Main Demo | `Main.java` |
Note: the "Class Explosion Problem — Visualised" pseudocode and the JDBC/SLF4J snippets shown in the article are illustrative only — they are not part of this repository's runnable example.
Article: https://ankurm.com/bridge-design-pattern-java/
All patterns: https://ankurm.com/design-patterns-java/

25
02-structural/bridge/Radio.java
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@@ -1,29 +1,18 @@
package bridge;
/**
* Concrete Implementor — a radio.
* Same Device interface, completely different internal behaviour.
*/
// Concrete Implementor #2: Radio
public class Radio implements Device {
private boolean on = false;
private int volume = 20;
private int channel = 1; // FM frequency index simplified
private int channel = 1;
@Override public boolean isEnabled() { return on; }
@Override public void enable() { on = true; System.out.println(" [Radio] Powered ON"); }
@Override public void disable() { on = false; System.out.println(" [Radio] Powered OFF"); }
@Override
public int getVolume() { return volume; }
@Override
public void setVolume(int percent) {
@Override public int getVolume() { return volume; }
@Override public void setVolume(int percent) {
this.volume = Math.max(0, Math.min(100, percent));
System.out.println(" [Radio] Volume set to " + this.volume);
}
@Override public int getChannel() { return channel; }
@Override public void setChannel(int ch) { this.channel = ch; System.out.println(" [Radio] Frequency -> " + ch); }
@Override public String getName() { return "JBL Radio"; }
@Override public int getChannel() { return channel; }
@Override public void setChannel(int ch) { this.channel = ch; System.out.println(" [Radio] Frequency -> " + ch); }
@Override public String getName() { return "JBL Radio"; }
}

18
02-structural/bridge/RemoteControl.java
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@@ -1,22 +1,18 @@
package bridge;
/**
* Abstraction — the remote control. It holds a reference to a Device
* (the "bridge") and delegates all real work to it.
* Abstraction — the remote control.
*
* The key: RemoteControl doesn't care whether it talks to a TV or Radio.
* It holds a Device and calls Device methods. That's the bridge.
* Key point: RemoteControl holds a Device (the bridge) and delegates
* all actual work to it. It adds higher-level semantics on top:
* "togglePower" instead of separate enable()/disable() calls.
*/
public class RemoteControl {
// The bridge — link from Abstraction to Implementation
protected Device device;
protected Device device; // THE BRIDGE
public RemoteControl(Device device) {
this.device = device;
System.out.println("Remote paired with: " + device.getName());
}
// User action → device operation translation
public void togglePower() {
if (device.isEnabled()) {
device.disable();
@@ -24,10 +20,8 @@ public class RemoteControl {
device.enable();
}
}
public void volumeUp() { device.setVolume(device.getVolume() + 10); }
public void volumeDown() { device.setVolume(device.getVolume() - 10); }
public void channelUp() { device.setChannel(device.getChannel() + 1); }
public void channelDown() { device.setChannel(device.getChannel() - 1); }
}

23
02-structural/bridge/TV.java
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@@ -1,29 +1,18 @@
package bridge;
/**
* Concrete Implementor — a television.
* Contains device-specific logic for a TV.
*/
// Concrete Implementor #1: Television
public class TV implements Device {
private boolean on = false;
private int volume = 30;
private int channel = 1;
@Override public boolean isEnabled() { return on; }
@Override public void enable() { on = true; System.out.println(" [TV] Powered ON"); }
@Override public void disable() { on = false; System.out.println(" [TV] Powered OFF"); }
@Override
public int getVolume() { return volume; }
@Override
public void setVolume(int percent) {
@Override public int getVolume() { return volume; }
@Override public void setVolume(int percent) {
this.volume = Math.max(0, Math.min(100, percent));
System.out.println(" [TV] Volume set to " + this.volume);
}
@Override public int getChannel() { return channel; }
@Override public void setChannel(int ch) { this.channel = ch; System.out.println(" [TV] Channel -> " + ch); }
@Override public String getName() { return "Samsung TV"; }
@Override public int getChannel() { return channel; }
@Override public void setChannel(int ch) { this.channel = ch; System.out.println(" [TV] Channel -> " + ch); }
@Override public String getName() { return "Samsung TV"; }
}

18
README.md
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@@ -197,6 +197,24 @@ javac 02-structural/adapter/*.java -d out/adapter
java -cp out/adapter adapter.Main
```
### Bridge (`02-structural/bridge/`)
| Post Section | File(s) |
|---|---|
| Step 1 — The Implementor Interface | `Device.java` |
| Step 2 — Concrete Implementors (TV and Radio) | `TV.java`, `Radio.java` |
| Step 3 — The Abstraction (RemoteControl) | `RemoteControl.java` |
| Step 4 — Refined Abstraction (AdvancedRemote) | `AdvancedRemote.java` |
| Wiring It Together: Main Demo | `Main.java` |
Note: the "Class Explosion Problem — Visualised" pseudocode and the JDBC/SLF4J snippets are illustrative only — they are not part of this repository's runnable example.
Run it:
```bash
javac 02-structural/bridge/*.java -d out/bridge
java -cp out/bridge bridge.Main
```
## Reference
- *Design Patterns: Elements of Reusable Object-Oriented Software* — Gamma, Helm, Johnson, Vlissides