Does a foreach Java loop create a new object?

Will Java create a new object every time a foreach loop is introduced? I'm not talking about every iteration, but if you have a foreach loop that is used multiple times, is it created every time?

A simple example:

for(Object o : Objects)
{
    for(Object p : Objects2)
    {
    }
}

Could there be only one pper run or create pfor each Object o? Does the garbage collector need to return an object from the foreach loop every time it exits?

In particular, I am writing Android code based on Android. It will iterate over all game objects with a given speed per second or as fast as it can, depending on the circumstances.

This may be a case of premature optimization, but if using an explicit loop foror whilecan guarantee that I will not have excessive garbage collection from my loops, then I can set this as the coding standard for the project.

More specific:

public void update()
{
    for(GameObject gObj : gameObjects)
    {
        gObj.update();
    }
}

C update()is called from a thread designed to make calls based on the time I described earlier.

Update: I ask if a new pone is being created for everyone oat Objects. Not if it copies objects to Objects2. Also, VM need to create a new Reference p, and then assemble this link between iterations of the outter loop? And, more specifically, in my case, does it collect a link between method calls?

Update: . ?

//Loop just to have it run a number of times
//Could be running the inner foreach numerous time for any reason
for(int i = 0; i < 1000; i++)
{
    for(Object o : Objects)
    {
        o.update();
    }
}

.

Iterator<Object> iter;
//Loop just to have it run a number of times
//Could be running the inner foreach numerous time for any reason
for(int i = 0; i < 1000; i++)
{
    iter = Objects.iterator();

    while(iter.hasNext());
    {
        iter.getNext().update();
    }
}

Update: :

import java.util.ArrayList;
import java.util.Iterator;


public class TestLoops
{
    public static Iterator<Object> it;
    public static ArrayList<Object> objects;

    public static void main(String... args)
    {
        objects = new ArrayList<Object>();

        it = objects.iterator();
        it = objects.iterator();

            //Every time we start a foreach loop, does it creates a new reference?
        Iterator<Object> newIt1 = objects.iterator();
        Iterator<Object> newIt2 = objects.iterator();       

    }
}

-:

public class TestLoops {
public static java.util.Iterator<java.lang.Object> it;

public static java.util.ArrayList<java.lang.Object> objects;

public TestLoops();

    Code:
       0: aload_0
       1: invokespecial #1                  // Method java/lang/Object."<init>":()V
       4: return

  public static void main(java.lang.String...);
    Code:
       0: new           #2                  // class java/util/ArrayList
       3: dup
       4: invokespecial #3                  // Method java/util/ArrayList."<init>":()V
       7: putstatic     #4                  // Field objects:Ljava/util/ArrayList;
      10: getstatic     #4                  // Field objects:Ljava/util/ArrayList;
      13: invokevirtual #5                  // Method java/util/ArrayList.iterator:()Ljava/util/Iterator;
      16: putstatic     #6                  // Field it:Ljava/util/Iterator;
      19: getstatic     #4                  // Field objects:Ljava/util/ArrayList;
      22: invokevirtual #5                  // Method java/util/ArrayList.iterator:()Ljava/util/Iterator;
      25: putstatic     #6                  // Field it:Ljava/util/Iterator;
      28: getstatic     #4                  // Field objects:Ljava/util/ArrayList;
      31: invokevirtual #5                  // Method java/util/ArrayList.iterator:()Ljava/util/Iterator;
      34: astore_1
      35: getstatic     #4                  // Field objects:Ljava/util/ArrayList;
      38: invokevirtual #5                  // Method java/util/ArrayList.iterator:()Ljava/util/Iterator;
      41: astore_2
      42: return
}
+5
2

, for-each. :

for(Object o : Objects)
{
    for(Object p : Objects2)
    {
    }
}

:

for(Iterator<Object> iter = Objects.iterator(); iter.hasNext();)
{
    Object o = iter.next();
    for(Iterator<Object> iter2 = Objects2.iterator(); iter2.hasNext();)
    {
        Object p = iter2.next();
    }
}

iter2, , Objects?

, Objects2. o? , Objects2.iterator() . , Iterable#iterator() , , Objects2.iterator() Iterator . , Objects2 ( iter2) .

.


?

. for (aka for-each loop) - . -, , . :

package com.stackoverflow;

import java.util.Iterator;

public class Question14640184
{
    public void enhancedForLoop(Iterable<Object> objects1, Iterable<Object> objects2)
    {
        for(Object o1 : objects1)
        {
            for(Object o2 : objects2)
            {
                // do something
            }
        }
    }

    public void iteratorForLoop(Iterable<Object> objects1, Iterable<Object> objects2)
    {
        for(Iterator<Object> iter1 = objects1.iterator(); iter1.hasNext();)
        {
            Object o1 = iter1.next();
            for(Iterator<Object> iter2 = objects2.iterator(); iter2.hasNext();)
            {
                Object o2 = iter2.next();
            }
        }
    }
}

Compile:

 javac Question14640184.java
 javap -c Question14640184
Compiled from "Question14640184.java"
public class com.stackoverflow.Question14640184 extends java.lang.Object{
public com.stackoverflow.Question14640184();
  Code:
   0:   aload_0
   1:   invokespecial   #1; //Method java/lang/Object."<init>":()V
   4:   return

public void enhancedForLoop(java.lang.Iterable, java.lang.Iterable);
  Code:
   0:   aload_1
   1:   invokeinterface #2,  1; //InterfaceMethod java/lang/Iterable.iterator:()Ljava/util/Iterator;
   6:   astore_3
   7:   aload_3
   8:   invokeinterface #3,  1; //InterfaceMethod java/util/Iterator.hasNext:()Z
   13:  ifeq    57
   16:  aload_3
   17:  invokeinterface #4,  1; //InterfaceMethod java/util/Iterator.next:()Ljava/lang/Object;
   22:  astore  4
   24:  aload_2
   25:  invokeinterface #2,  1; //InterfaceMethod java/lang/Iterable.iterator:()Ljava/util/Iterator;
   30:  astore  5
   32:  aload   5
   34:  invokeinterface #3,  1; //InterfaceMethod java/util/Iterator.hasNext:()Z
   39:  ifeq    54
   42:  aload   5
   44:  invokeinterface #4,  1; //InterfaceMethod java/util/Iterator.next:()Ljava/lang/Object;
   49:  astore  6
   51:  goto    32
   54:  goto    7
   57:  return

public void iteratorForLoop(java.lang.Iterable, java.lang.Iterable);
  Code:
   0:   aload_1
   1:   invokeinterface #2,  1; //InterfaceMethod java/lang/Iterable.iterator:()Ljava/util/Iterator;
   6:   astore_3
   7:   aload_3
   8:   invokeinterface #3,  1; //InterfaceMethod java/util/Iterator.hasNext:()Z
   13:  ifeq    57
   16:  aload_3
   17:  invokeinterface #4,  1; //InterfaceMethod java/util/Iterator.next:()Ljava/lang/Object;
   22:  astore  4
   24:  aload_2
   25:  invokeinterface #2,  1; //InterfaceMethod java/lang/Iterable.iterator:()Ljava/util/Iterator;
   30:  astore  5
   32:  aload   5
   34:  invokeinterface #3,  1; //InterfaceMethod java/util/Iterator.hasNext:()Z
   39:  

, , .

, .

, .

+6

, Iterable. , . , . , , , . .

, , - , Iterable , :

for (Object o : xyz.getIterable())

for-each, .

+2

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