From bd28a1e622f7edaf57f15b15aeacc1f2231f9d5a Mon Sep 17 00:00:00 2001 From: Yan Wittmann <2121578@stud.hs-mannheim.de> Date: Thu, 1 Dec 2022 16:02:54 +0100 Subject: [PATCH] Initial Commit with existing project materials --- pom.xml | 17 ++++ src/main/java/io/dama/ffi/hoh/Main.java | 41 +++++++++ .../java/io/dama/ffi/hoh/SimplifiedList.java | 56 ++++++++++++ .../ffi/hoh/ThreadsafeSimplifiedList.java | 90 +++++++++++++++++++ 4 files changed, 204 insertions(+) create mode 100644 pom.xml create mode 100644 src/main/java/io/dama/ffi/hoh/Main.java create mode 100644 src/main/java/io/dama/ffi/hoh/SimplifiedList.java create mode 100644 src/main/java/io/dama/ffi/hoh/ThreadsafeSimplifiedList.java diff --git a/pom.xml b/pom.xml new file mode 100644 index 0000000..d3ca212 --- /dev/null +++ b/pom.xml @@ -0,0 +1,17 @@ + + + 4.0.0 + + pp.hsma + pp.A4 + 1.0-SNAPSHOT + + + UTF-8 + 11 + 11 + + + diff --git a/src/main/java/io/dama/ffi/hoh/Main.java b/src/main/java/io/dama/ffi/hoh/Main.java new file mode 100644 index 0000000..82db479 --- /dev/null +++ b/src/main/java/io/dama/ffi/hoh/Main.java @@ -0,0 +1,41 @@ +package io.dama.ffi.hoh; + +public class Main { + static SimplifiedList list; + + static Runnable sliceSum(int start, int end, int expected) { + return () -> { + var sum = 0; + for (var i = start; i < end; i++) { + sum += list.get(i); + } + if (sum != expected) { + System.out.println("Fehler in " + + Thread.currentThread().getName() + ": " + sum); + } + }; + } + + public static void main(String... args) throws InterruptedException { + list = new ThreadsafeSimplifiedList<>(); + for (int i = 0; i < 5000; i++) { + list.add(i); + } + var thread0 = new Thread(sliceSum(0, 1250, 780625)); + var thread1 = new Thread(sliceSum(1250, 2500, 2343125)); + var thread2 = new Thread(sliceSum(2500, 3750, 3905625)); + var thread3 = new Thread(sliceSum(3750, 5000, 5468125)); + var start = System.currentTimeMillis(); + thread0.start(); + thread1.start(); + thread2.start(); + thread3.start(); + thread0.join(); + thread1.join(); + thread2.join(); + thread3.join(); + System.out.printf("%s: %d ms\n", list.getClass().toString(), + System.currentTimeMillis() - start); + } + +} diff --git a/src/main/java/io/dama/ffi/hoh/SimplifiedList.java b/src/main/java/io/dama/ffi/hoh/SimplifiedList.java new file mode 100644 index 0000000..5fc52c3 --- /dev/null +++ b/src/main/java/io/dama/ffi/hoh/SimplifiedList.java @@ -0,0 +1,56 @@ +package io.dama.ffi.hoh; + +public interface SimplifiedList { + + /** + * Returns the element at the specified position in this list. + * + * @param index index of the element to return + * @return the element at the specified position in this list + */ + public T get(int index); + + /** + * Appends the specified element to the end of this list. There are no + * limitations on what elements may be added to this list. + * + * @param element element to be appended to this list + * @return true + * @see java.util.Collection#add(Object) + * + */ + public boolean add(T element); + + /** + * Replaces the element at the specified position in this list with the + * specified element. + * + * @param index index of the element to replace + * @param element element to be stored at the specified position + * @return the element previously at the specified position + */ + public T set(int index, T element); + + /** + * Returns true if this list contains no elements. + * + * @return true if this list contains no elements + */ + public boolean isEmpty(); + + /** + * delayed passing through of parameter + * + * @param element element to pass through + * @return passed though element + * + */ + public default T delay(T element) { + try { + Thread.sleep(10); + } catch (InterruptedException ex) { + Thread.currentThread().interrupt(); + } + return element; + } +} diff --git a/src/main/java/io/dama/ffi/hoh/ThreadsafeSimplifiedList.java b/src/main/java/io/dama/ffi/hoh/ThreadsafeSimplifiedList.java new file mode 100644 index 0000000..bbc53aa --- /dev/null +++ b/src/main/java/io/dama/ffi/hoh/ThreadsafeSimplifiedList.java @@ -0,0 +1,90 @@ +package io.dama.ffi.hoh; + +public class ThreadsafeSimplifiedList implements SimplifiedList { + private Node first; + + private class Node { + private U element; + private Node prev; + private Node next; + + private Node(U element, Node prev, Node next) { + super(); + this.element = element; + this.prev = prev; + this.next = next; + } + } + + public ThreadsafeSimplifiedList() { + super(); + this.first = null; + } + + /** + * Returns the element at the specified position in this list. + * + * @param index index of the element to return + * @return the element at the specified position in this list + */ + @Override + public synchronized T get(int index) { + var ptr = this.first; + for (var j = 0; j < index; j++) { + ptr = ptr.next; + } + return delay(ptr.element); + } + + /** + * Appends the specified element to the end of this list. There are no + * limitations on what elements may be added to this list. + * + * @param element element to be appended to this list + * @return true + * @see java.util.Collection#add(Object) + * + */ + @Override + public synchronized boolean add(T element) { + if (this.first != null) { + var ptr = this.first; + while (ptr.next != null) { + ptr = ptr.next; + } + ptr.next = new Node<>(element, ptr, null); + } else { + this.first = new Node<>(element, null, null); + } + return true; + } + + /** + * Replaces the element at the specified position in this list with the + * specified element. + * + * @param index index of the element to replace + * @param element element to be stored at the specified position + * @return the element previously at the specified position + */ + @Override + public synchronized T set(int index, T element) { + var ptr = this.first; + for (var j = 0; j < index; j++) { + ptr = ptr.next; + } + var prevElement = ptr.element; + ptr.element = element; + return prevElement; + } + + /** + * Returns true if this list contains no elements. + * + * @return true if this list contains no elements + */ + @Override + public synchronized boolean isEmpty() { + return this.first == null; + } +}