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docs: #590 add explanation for bytecode pattern (#1687)

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Type: docs and refactoring

Co-authored-by: Subhrodip Mohanta <hello@subho.xyz>
This commit is contained in:
Ilkka Seppälä
2021-03-22 08:49:46 +02:00
committed by GitHub
parent 7ac468db20
commit c413e0902e
10 changed files with 277 additions and 103 deletions
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42
bytecode/src/main/java/com/iluwatar/bytecode/App.java
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@ -49,33 +49,21 @@ public class App {
*/
public static void main(String[] args) {
var wizard = new Wizard();
wizard.setHealth(45);
wizard.setAgility(7);
wizard.setWisdom(11);
var vm = new VirtualMachine(
new Wizard(45, 7, 11, 0, 0),
new Wizard(36, 18, 8, 0, 0));
var vm = new VirtualMachine();
vm.getWizards()[0] = wizard;
String literal = "LITERAL 0";
interpretInstruction(literal, vm);
interpretInstruction(literal, vm);
interpretInstruction("GET_HEALTH", vm);
interpretInstruction(literal, vm);
interpretInstruction("GET_AGILITY", vm);
interpretInstruction(literal, vm);
interpretInstruction("GET_WISDOM ", vm);
interpretInstruction("ADD", vm);
interpretInstruction("LITERAL 2", vm);
interpretInstruction("DIVIDE", vm);
interpretInstruction("ADD", vm);
interpretInstruction("SET_HEALTH", vm);
}
private static void interpretInstruction(String instruction, VirtualMachine vm) {
vm.execute(InstructionConverterUtil.convertToByteCode(instruction));
var stack = vm.getStack();
LOGGER.info(instruction + String.format("%" + (12 - instruction.length()) + "s", "") + stack);
vm.execute(InstructionConverterUtil.convertToByteCode("LITERAL 0"));
vm.execute(InstructionConverterUtil.convertToByteCode("LITERAL 0"));
vm.execute(InstructionConverterUtil.convertToByteCode("GET_HEALTH"));
vm.execute(InstructionConverterUtil.convertToByteCode("LITERAL 0"));
vm.execute(InstructionConverterUtil.convertToByteCode("GET_AGILITY"));
vm.execute(InstructionConverterUtil.convertToByteCode("LITERAL 0"));
vm.execute(InstructionConverterUtil.convertToByteCode("GET_WISDOM"));
vm.execute(InstructionConverterUtil.convertToByteCode("ADD"));
vm.execute(InstructionConverterUtil.convertToByteCode("LITERAL 2"));
vm.execute(InstructionConverterUtil.convertToByteCode("DIVIDE"));
vm.execute(InstructionConverterUtil.convertToByteCode("ADD"));
vm.execute(InstructionConverterUtil.convertToByteCode("SET_HEALTH"));
}
}

22
bytecode/src/main/java/com/iluwatar/bytecode/Instruction.java
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@ -33,17 +33,17 @@ import lombok.Getter;
@Getter
public enum Instruction {
LITERAL(1),
SET_HEALTH(2),
SET_WISDOM(3),
SET_AGILITY(4),
PLAY_SOUND(5),
SPAWN_PARTICLES(6),
GET_HEALTH(7),
GET_AGILITY(8),
GET_WISDOM(9),
ADD(10),
DIVIDE(11);
LITERAL(1), // e.g. "LITERAL 0", push 0 to stack
SET_HEALTH(2), // e.g. "SET_HEALTH", pop health and wizard number, call set health
SET_WISDOM(3), // e.g. "SET_WISDOM", pop wisdom and wizard number, call set wisdom
SET_AGILITY(4), // e.g. "SET_AGILITY", pop agility and wizard number, call set agility
PLAY_SOUND(5), // e.g. "PLAY_SOUND", pop value as wizard number, call play sound
SPAWN_PARTICLES(6), // e.g. "SPAWN_PARTICLES", pop value as wizard number, call spawn particles
GET_HEALTH(7), // e.g. "GET_HEALTH", pop value as wizard number, push wizard's health
GET_AGILITY(8), // e.g. "GET_AGILITY", pop value as wizard number, push wizard's agility
GET_WISDOM(9), // e.g. "GET_WISDOM", pop value as wizard number, push wizard's wisdom
ADD(10), // e.g. "ADD", pop 2 values, push their sum
DIVIDE(11); // e.g. "DIVIDE", pop 2 values, push their division
private final int intValue;

26
bytecode/src/main/java/com/iluwatar/bytecode/VirtualMachine.java
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@ -24,12 +24,15 @@
package com.iluwatar.bytecode;
import java.util.Stack;
import java.util.concurrent.ThreadLocalRandom;
import lombok.Getter;
import lombok.extern.slf4j.Slf4j;
/**
* Implementation of virtual machine.
*/
@Getter
@Slf4j
public class VirtualMachine {
private final Stack<Integer> stack = new Stack<>();
@ -37,12 +40,21 @@ public class VirtualMachine {
private final Wizard[] wizards = new Wizard[2];
/**
* Constructor.
* No-args constructor.
*/
public VirtualMachine() {
for (var i = 0; i < wizards.length; i++) {
wizards[i] = new Wizard();
}
wizards[0] = new Wizard(randomInt(3, 32), randomInt(3, 32), randomInt(3, 32),
0, 0);
wizards[1] = new Wizard(randomInt(3, 32), randomInt(3, 32), randomInt(3, 32),
0, 0);
}
/**
* Constructor taking the wizards as arguments.
*/
public VirtualMachine(Wizard wizard1, Wizard wizard2) {
wizards[0] = wizard1;
wizards[1] = wizard2;
}
/**
@ -57,6 +69,7 @@ public class VirtualMachine {
case LITERAL:
// Read the next byte from the bytecode.
int value = bytecode[++i];
// Push the next value to stack
stack.push(value);
break;
case SET_AGILITY:
@ -107,6 +120,7 @@ public class VirtualMachine {
default:
throw new IllegalArgumentException("Invalid instruction value");
}
LOGGER.info("Executed " + instruction.name() + ", Stack contains " + getStack());
}
}
@ -133,4 +147,8 @@ public class VirtualMachine {
public int getAgility(int wizard) {
return wizards[wizard].getAgility();
}
private int randomInt(int min, int max) {
return ThreadLocalRandom.current().nextInt(min, max + 1);
}
}

5
bytecode/src/main/java/com/iluwatar/bytecode/Wizard.java
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@ -23,6 +23,7 @@
package com.iluwatar.bytecode;
import lombok.AllArgsConstructor;
import lombok.Getter;
import lombok.Setter;
import lombok.extern.slf4j.Slf4j;
@ -31,16 +32,15 @@ import lombok.extern.slf4j.Slf4j;
* This class represent game objects which properties can be changed by instructions interpreted by
* virtual machine.
*/
@AllArgsConstructor
@Setter
@Getter
@Slf4j
public class Wizard {
private int health;
private int agility;
private int wisdom;
private int numberOfPlayedSounds;
private int numberOfSpawnedParticles;
@ -53,5 +53,4 @@ public class Wizard {
LOGGER.info("Spawning particles");
numberOfSpawnedParticles++;
}
}

2
bytecode/src/main/java/com/iluwatar/bytecode/util/InstructionConverterUtil.java
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@ -73,6 +73,4 @@ public class InstructionConverterUtil {
return false;
}
}
}