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For if loop wont loop: any pointers to why that might be?

This is supposed to loop 24 times; it does not, and I'm pretty confused as to why. Please help me various Kenobis out there :
private boolean simpleMove(Board bd)
{
int b = rn.nextInt(3);
for (int i = 0; i < 24; i++) {
if (bd.isVacant(i) && rul.isLegalMove(tigerLocs[b], i)) {
bd.swap(tigerLocs[b],i);
bd.setTiger(i);
tigerLocs[b] = i;
System.out.println(i);
return true;
}
else {
System.out.println(i);
}
}
System.out.println("invalid");
return false;

As the comments point out your loop will execute a maximum of 24 times.
But the return statement inside the if statement may cause it to return 'early'.
It looks like it's some kind of board game thing.
The board appears to have 24 'squares' and it makes the first legal move and returns true.
If it fails to find a legal move, it returns false.
I can't confirm the logic overall but that rationale seems sound:
If there's a move available, take it and return true.
If no move is available, make no move and return false.

If you expected it to continue, even after finding a "valid" move, then simply store the fact that a valid move has been found. This can be done in a separate boolean variable:
private boolean simpleMove(Board bd) {
int b = rn.nextInt(3);
boolean valid = false; // until proven otherwise below
for (int i = 0; i < 24; i++) {
if (bd.isVacant(i) && rul.isLegalMove(tigerLocs[b], i)) {
bd.swap(tigerLocs[b],i);
bd.setTiger(i);
tigerLocs[b] = i;
valid = true;
}
System.out.println(i); // why output HERE when we have a return value?
}
if (!valid) {
System.out.println("invalid"); // why output HERE when we have a return value?
}
return valid;
}
It's unclear if multiple "valid" moves could be found, and whether that would be a problem when you "swap" or not. If there is only ever one possible move, then there would be no need to continue iterating with the for loop; simply return in the body like you were doing.

Find bug in implementation of algorithm that finds minimum of an array of integers

Recently, I tried to write a Java program which searches for the minimum of an array.
I tried to write it in a different way, I know there are more simple ways to do that but I want to know why my program does not work.
Here is the source code :
public int minimum(int [] t) {
int min,i,j;
i=j=t.length/2;
min=t[t.length/2];
while(j!=0 || i!=t.length-1) {
while( t[i]>=min) {
i++;
if(i==t.length) {
i=t.length-1;
continue;
}
}
while(t[j]>=min) {
j--;
if(j==-1) {
j=0;
continue;
}
}
if(t[i]<=min && t[j]<=min) {
if(t[i]<=t[j]) min=t[i];
else min=t[j];
}
}
return min;
}
Thanks.

Before you read the answer you should try debugging your code to figure this out by yourself.
I think your code loops infinitely in one of those inner while loops because the end condition
if(i==t.length) {
i=t.length-1;
continue;
}
only resets the i one step back and the continue restarts the while loop. You probably meant to have the break keyword there instead of the continue in which case your code will continue with the other inner while loop.

there is some logic errors in my code , and it get infinitely going through the two loops , i fixed the loops by changing continue with break and i modify the last condition by setting || instead of && (that was a logic mistake), and it works now .
thanks guys.
here is the new source code:
public int minimum(int [] t) {
int min,i,j;
i=j=t.length/2;
min=t[t.length/2];
while(j!=0 || i!=t.length-1) {
while( t[i]>=min) {
i++;
if(i==t.length) {
i=t.length-1;
break;
}
}
while(t[j]>=min) {
j--;
if(j==-1) {
j=0;
break;
}
}
if(t[i]<=min || t[j]<=min) {
if(t[i]<=t[j]) min=t[i];
else min=t[j];
}
}
return min;
}

for loop decrease variable in loop

I want to decrease the variable loop in for loop. What can I do?
When I do loop--.It will forever loop happened
for (int loop=0;loop<number.length-1;loop++)
{
if (number[loop] != number[loop+1])
{
if (loop > 0 && freq_array[loop-1]== 1 )
{
loop--; //this line
continue;
}
freq=1;
freq_array[loop]=freq;
}
else if (number[loop] == number[loop+1])
{
freq++;
freq_array[loop]=freq;
}
}
#cameron1024 advice me to use while loop but it has forever loop anyway?
while (loop<number.length-1)
{
if (number[loop] != number[loop+1])
{
if (loop > 0 && freq_array[loop-1]== 1 )
{
continue;
}
else
{
freq=1;
freq_array[loop]=freq;
loop++;
}
}
else
{
freq++;
freq_array[loop]=freq;
loop++;
}
}

Firstly, read https://docs.oracle.com/javase/tutorial/java/nutsandbolts/for.html
Secondly, a for loop is just a while loop with decoration. For example:
for (<initializer>; <termination>; <increment>) {
<loop body>
}
is identical (with minor scope changes) to:
<initializer>;
while (<termination>) {
<loop body>
<termination>
}
The reason it is looping forever is that you have not changed your termination condition to match the fact that the variable is now decreasing. Your termination condition checks that loop does not go above a certain value. And since loop only ever decreases, that condition is always satisfied, and so the loop continues infinitely.
P.S. avoid naming variables like_this in java, they are typically done likeThis

i think you want this.
for (int loop = number.length - 1; loop > 0; loop--)

If you mean you want to count down:
Just do for(int i=10;i>=0;i--)
int i = 10 makes a new int initialised with 10
The next part is your loops exit condition.
as long a i>=10,the loop will run
And lastly i-- decrement the variable i
Your loop is infinite because the loop++ in the making of the loop and your loop-- are falling together creating a
int i = 1;
while(i < 10) {
i++;
i--;
}

while (loop<number.length-1)
{
if (number[loop] != number[loop+1])
{
freq=1;
freq_array[loop]=freq;
loop++;
}
else
{
freq++;
if (loop > 0 && freq_array[loop-1]== 1 )
{
freq_array[loop-1]=freq;
}
else
{
freq_array[loop]=freq;
}
loop++;
}
}
I'm done now thank you every one.

Break while loop only when all conditions in for loop are met

I would like to break a while loop only when all of the "bots" are upright. (*These bots being referred to are mini USB robots).
.upRight() returns true when a bot is standing and false when not.
public static boolean checkSomething() throws ... {
while (true) {
for (i = 0; i < bots; i++) { // bots = 2
if (!theMainBots[i].isUpright()) {
...
Thread.sleep(1000);
}
else {
return true;
}
}
}
The issue I'm facing, is that if the isUpright() method returns true for the first "bot", then all other bots are left unchecked and may return false. The intention is to wait for the user to place the bot in an upright position before proceeding.

You should check all the bots first, then act on the result. Don't try to act on the result inside the check loop.
Also, since the code doesn't return until all bots are upright, the method is misnamed and shouldn't return a value.
public static void waitUntilAllUpright() throws InterruptedException {
for (;;) { // forever loop
boolean allUpright = true;
for (i = 0; i < bots; i++) {
if (! theBots[i].isUpright()) {
allUpright = false;
break;
}
}
if (allUpright)
return;
System.out.println("Please ensure I'm upright");
Thread.sleep(500);
} // loop back to check all bots again
}

If you want to wait until the user makes the bot upright you could change the if to a while:
while (true) {
for (i = 0; i < bots; i++) { // bots = 2
while(!theBots[i].isUpright()) {
System.out.println("Please ensure I'm upright");
Thread.sleep(500);
}
}
return true;
}
This will loop through each element in the Array and while any given bot is not upright, it will loop and sleep until the bot is turned upright. In which case, you do not need to while(true) loop:
public static boolean checkUpright() throws InterruptedException {
for (i = 0; i < bots; i++) { // bots = 2
while(!theBots[i].isUpright()) {
System.out.println("Please ensure I'm upright");
Thread.sleep(500);
}
}
return true;
}

One way to achieve this, is using a variable that will determine when to leave the loop. Your problem here, is that you also need to change your for loop for a while loop. Why is that? Because you don't know if the bot you just checked was moved or not. Also, the outer loop is unnecessarily, unless you wanted to recheck again. So the code would end looking something like this.
public static boolean checkUpright() throws InterruptedException {
int counter = 0;
while (counter <= theBots.length) { // bots = 2
if (!theBots[i].isUpright()) {
System.out.println("Please ensure I'm upright");
Thread.sleep(500);
} else {
counter ++;
}
}
}

The context is not completely clear, but mixing logical control with user interaction might be the problem. Perhaps this approach might work:
public static boolean checkUpright() throws InterruptedException {
while (!areAllBotsUpright()) {
System.out.println("Please ensure I'm upright");
Thread.sleep(500);
}
}
public static boolean areAllBotsUpright() {
for (i = 0; i < bots; i++) {
if (!theBots[i].isUpright()) {
return false;
}
}
return true;
}

you can create a list from array of bots , iterate over this list using iterator
if a particular bot is upright , remove it from this list using iterator.remove.
outer while will run until list is not empty.
public static boolean checkUpright() {
ArrayList<Bot> notUprightBots= (ArrayList<Bot>) Arrays.asList(theBots);
while (!notUprightBots.isEmpty()) {
Iterator<Bot> iterator=notUprightBots.iterator();
while(iterator.hasNext()){
Bot bot=iterator.next();
if (!bot.isUpright()) {
System.out.println("Please ensure I'm upright");
try{
Thread.sleep(500);
}catch(InterruptedException e){
}
}else {
iterator.remove();
}
}
}
return true;
}

how to jump from inner loop to outer loop

Here is the structure of my program:
for(loop1){
if(condition1)
{
for(loop2)
{
for(loop3)
{
if(condition1_3)
{
As condition1_3 is true continue with loop2's next iteration,
No need to execute loop3's remaining iteration
}
else
{
As condition1_3 is false no need to execute remaining part of loop3 and
loop 2 but continue with loop1's remaining part i.e. condition1_1
}
}
}
}
if(condition1_1)
{
some code here
}
}
I know I have to use continue and break statement but don't understand exactly how?
Please tell me how to achieve this mechanism?

If I understand your question, you could use the labeled continue,
loop1: for (;;) {
if (condition1) {
loop2: for (;;) {
loop3: for (;;) {
if (condition1_3) {
continue loop2;
} else {
continue loop1;
}
}
}
}
}

You can do as follows:
for(loop1){
if(condition1)
{
for(loop2)
{
boolean flag=false;
for(loop3)
{
if(condition1_3)
{
break;
}
else
{
flag=true;
break;
}
}
if(flag)
break;
}
}
if(condition1_1)
{
some code here
}
}

Do like the following -
for(loop1){
boolean flag = false;
if(condition1)
{
for(loop2)
{
if(flag == true)
break;
for(loop3)
{
if(condition1_3)
{
break;
}
else
{
flag = true;
break;
}
}
}
}
if(condition1_1)
{
some code here
}
}

An option would be to use variables - but you have to think about correct setting of values:
boolean runFor1 = true;
boolean runFor2 = true;
boolean runFor3 = true;
for(loop1 && runFor1)
{
for(loop2 && runFor2)
{
for(loop3 && runFor3)
{
setRunForX here to skip/unskip loops
}
}
}
}

Have a exit flags which is set when you want to exit a particular loop and check in each respective loops whether to continue or exit.
boolean exitLoop2 = false;
for(loop1){
if(condition1)
{
for(loop2)
{
for(loop3)
{
if(condition1_3)
{
//As condition1_3 is true continue with loop2's next iteration,
//No need to execute loop3's remaining iteration
break;
}
else
{
//As condition1_3 is false no need to execute remaining part of loop3 and
//loop 2 but continue with loop1's remaining part i.e. condition1_1
exitLoop2 = true;
break;
}
}
if(exitLoop2)
{
break;
}
}
}
if(condition1_1)
{
some code here
}
}

To break out and not continue the loop3 use break; if (condition1_3) break; The break; statement only breaks out of the current loop i think, not the loop it is nested in.
Edit: Missread the question
To break out of both loops you can make a boolean flag before both loops and at the end of both loops have an if (breakOut) break; This will solv the question

I'm not really shure what do you mean exactly. For me it simply looks like you want to jump out of the loops if a specific condition is satisfied. So you can either can define a label for your loops and use the continue labelLoopX; statement or you can satisfy the exit condition of loop3 if condition1_3==true resp. the exit condition of loop3 and loop2 if condition1_3==false. e.g. if loop3 looks like for ( int i = 0; i < 10; i++ ) like this:
if(condition1_3){
//do something important
i=10; //sets i to 10 and condition i < 10 is unsatified
}
else{
//do some other important stuff
i=10; //satify loop3's exitcondition
j=10; //satify loop2's exitcondition
}