Im in the progress of working on a crappy little fight simulator as my first game in java. Ive got most of it done, but whenever i fight the slime i get an infinite loop. can somebody point out to me what i did wrong?

also any tips on making my code smoother and easier to read will be appreciated.

[source lang="java"]import java.io.*;
import java.util.*;

public class HelloWorld {

static String name;
static boolean gameStart = true;
static Scanner sc = new Scanner(System.in);

static int hero_health = 100;
static int hero_strength = 10;
static int hero_defense = 8;
static int hero_agility = 6;
static int hero_exp = 0;

static int s_health = 25;
static int s_strength = 3;
static int s_defense = 3;
static int s_agility = 1;


public static void main(String args[]){
System.out.println("What is your name?");
name = sc.next();
System.out.println("Welcome " + name);
System.out.println("Your stats: ");
System.out.println(hero_health + " health");
System.out.println(hero_strength + " strength");
System.out.println(hero_defense + " defense");
System.out.println(hero_agility + " agility");

startGame();
}
public static void startGame()
{
Scanner sc = new Scanner(System.in);

System.out.println("You awake in a tavern. You walk outside to hear commotion in the streets. " +
"From what you can gather, the princess of the kingdom has been kidnapped and has been taken to a " +
"nearby castle.");
System.out.println("You wander around the village asking where the castle is, hoping to make a few quick bucks."
+ "After a good hour, you learn that the castle is just outside the village, but it is guarded by a dragon");
System.out.println("Even though you are weak, you have slain dragons before. All you need is to train back to your normal level and fight the dragon");
System.out.println("Do you want to go outside of the village to train? Or would you rather relax at the tavern?");
System.out.println("Type '1' to rest or '2' to go fight monsters");
int start = sc.nextInt();

switch(start)
{
case 1:
System.out.println("You decide to return to the tavern to rest.");
hero_health = 100;
System.out.println("HEALTH RESTORED.");
break;
case 2:
System.out.println("You wander out of the town looking for a fight");
battleSlime();
break;
}
}

public static void fightTech()
{
boolean fight_tech = true;
int basedamage = hero_strength - s_defense;
final int LOWF = 1;
int damage = (int)(Math.random() * (basedamage - s_defense + 1)) + LOWF;
final int HIGHF = 20;
int ROLLF = (int)(Math.random() * 20) + 1;
int crithit = basedamage * 2;

while (fight_tech)
{
if (ROLLF <= 13)
{
System.out.println("You hit!");
s_health = s_health - damage;
System.out.println("You dealt " + damage + " damage to slime.");
System.out.println("Slime has " + s_health + " health left");
if (s_health == 0 || s_health < 0)
{
fight_tech = false;
Victory();
}
slimeAttack();
}
else if (ROLLF >= 14 && ROLLF <= 18)
{
System.out.println("Aww you missed!");
System.out.println("Slime has " + s_health + " health left");
slimeAttack();
}
else if (ROLLF >=19)
{
System.out.println("Critical hit!!!!!");
s_health = s_health - crithit;
System.out.println("Slime has " + s_health + " health left");
slimeAttack();
}
System.out.println("Slime has " + s_health + " health left");
}
}
public static void defendTech()
{
final int LOWD = 1;
final int HIGHD = 10;
final int ROLLD = (int)(Math.random() * (HIGHD - LOWD + 1)) + LOWD;
if (ROLLD <=3)
{
System.out.println("You avoided half the damage by blocking");

}
else if (ROLLD >=4 && ROLLD < 10)
{
System.out.println("Close but not close enough. You only blocked 25% of damage.");
}
else if (ROLLD == 10)
{
System.out.println("You managed to roll out of the way. Took no damage");
}
}
public static void runTech()
{
final int LOWR = 1;
final int HIGHR = 10;
final int ROLLR = (int)(Math.random() * (HIGHR - LOWR +1)) + LOWR;
if (ROLLR <= 10)
{
System.out.println("You successfully escaped");
}
else
{
System.out.println("Couldn't escape");
}
}
public static void battleSlime()
{
boolean battle_slime = true;

System.out.println("You've encountered a slime!!");
while (battle_slime)
{
System.out.println("Type 'F' to fight, 'D' to defend, or 'R' to run away); ");
switch('F')
{
case 'F':
fightTech();
break;
case 'D':
defendTech();
break;
case 'R':
break;
}
}
}
public static void slimeAttack()
{
int low = 1;
int high = 10;
int roll = (int)(Math.random() * 10);
int damage = hero_defense - s_strength;
if (roll <= 5)
{
hero_health = hero_health - damage;
System.out.println("Slime dealt " + damage + " damage.");
System.out.println("You have " + hero_health + " health left");
fightTech();
}
else
{
System.out.println("Slime missed!");
System.out.println("You have " + hero_health + " health left");
fightTech();
}
}
public static void slimeDead()
{

}
public static void Victory()
{
System.out.println("You've defeated the slime!");
}
}[/source]

huh. didnt show all the code


if (ROLLR <= 10)
{
System.out.println("You successfully escaped");
}
else
{
System.out.println("Couldn't escape");
}
}
public static void battleSlime()
{
boolean battle_slime = true;

System.out.println("You've encountered a slime!!");
while (battle_slime)
{
System.out.println("Type 'F' to fight, 'D' to defend, or 'R' to run away); ");
switch('F')
{
case 'F':
fightTech();
break;
case 'D':
defendTech();
break;
case 'R':
break;
}
}
}
public static void slimeAttack()
{
int low = 1;
int high = 10;
int roll = (int)(Math.random() * 10);
int damage = hero_defense - s_strength;
if (roll <= 5)
{
hero_health = hero_health - damage;
System.out.println("Slime dealt " + damage + " damage.");
System.out.println("You have " + hero_health + " health left");
fightTech();
}
else
{
System.out.println("Slime missed!");
System.out.println("You have " + hero_health + " health left");
fightTech();
}
}
public static void slimeDead()
{

}
public static void Victory()
{
System.out.println("You've defeated the slime!");
}
}


when i set battle_slime to false after its health reaches 0 it still gives the infinite loop

public static void battleSlime()
{
boolean battle_slime = true;


while (battle_slime)
{
System.out.println("Type 'F' to fight, 'D' to defend, or 'R' to run away");
switch('F')
{
case 'F':
fightTech();
break;
case 'D':
defendTech();
break;
case 'R':
break;
}
if (s_health == 0 || s_health < 0)
{
battle_slime = false;
Victory();
}
}
}


it was a problem with my switch in battleSlime(). but now it wont let me enter a response, it just terminates after i battleSlime starts

do i even need the while loops with the fight_tech if im just calling the method again from slimeAttack? i feel like i already have a loop just by repeatedly calling the methods back and forth until the slime dies

public static void fightTech()
{
boolean fight_tech = true;
int basedamage = hero_strength - s_defense;
final int LOWF = 1;
int damage = (int)(Math.random() * (basedamage - s_defense + 1)) + LOWF;
final int HIGHF = 20;
int ROLLF = (int)(Math.random() * 20) + 1;
int crithit = basedamage * 2;

while (fight_tech)
{
if (ROLLF = 14 && ROLLF =19)
{
System.out.println("Critical hit!!!!!");
s_health = s_health - crithit;
System.out.println("Slime has " + s_health + " health left");
slimeAttack();
}
System.out.println("Slime has " + s_health + " health left");
}
}
public static void defendTech()
{
final int LOWD = 1;
final int HIGHD = 10;
final int ROLLD = (int)(Math.random() * (HIGHD - LOWD + 1)) + LOWD;
if (ROLLD =4 && ROLLD < 10)
{
System.out.println("Close but not close enough. You only blocked 25% of damage.");
}
else if (ROLLD == 10)
{
System.out.println("You managed to roll out of the way. Took no damage");
}
}

a few things i saw:
In fight_tech() :
the fight_tech boolean is never set to false.
You have an if check that sets ROLLF 14 and 19 every iteration

in defense_tech();
simialr situation you have an if check that sets ROLLD to 4 every iteration

fixed it. it was a problem with the switch and i forgot to initialize a scanner to get input. it works fine now!