commit 5683751a990fd963ed93669d034100c7d78245ff Author: Sebastian Brosch Date: Sat Oct 12 23:38:53 2024 +0200 solution for smart bank diff --git a/.editorconfig b/.editorconfig new file mode 100644 index 0000000..26ba19b --- /dev/null +++ b/.editorconfig @@ -0,0 +1,9 @@ +root = true + +[*] +charset = utf-8 +indent_style = space + +[*.java] +indent_size = 2 +insert_final_newline = true \ No newline at end of file diff --git a/.gitignore b/.gitignore new file mode 100644 index 0000000..1644e00 --- /dev/null +++ b/.gitignore @@ -0,0 +1,3 @@ +.vscode/ +.gradle/ +build/ \ No newline at end of file diff --git a/README.md b/README.md new file mode 100644 index 0000000..3a13b46 --- /dev/null +++ b/README.md @@ -0,0 +1 @@ +# VL-PAR-PROG \ No newline at end of file diff --git a/VL03-02-01/build.gradle b/VL03-02-01/build.gradle new file mode 100644 index 0000000..7b59c96 --- /dev/null +++ b/VL03-02-01/build.gradle @@ -0,0 +1,22 @@ +apply plugin: 'java' + +apply plugin: 'eclipse' +// Run 'gradlew eclipse' for the eclipse project + +apply plugin: 'idea' +// Run 'gradle idea' for the IntelliJ idea project (no longer necessary in idea 13) + +// Netbeans: See http://plugins.netbeans.org/plugin/44510/gradle-support + + +repositories { + mavenCentral() +} + + +dependencies { + implementation 'commons-lang:commons-lang:2.6' + testImplementation 'junit:junit:4.11' + testImplementation 'org.easytesting:fest-assert:1.4' +} + diff --git a/VL03-02-01/gradle/wrapper/gradle-wrapper.jar b/VL03-02-01/gradle/wrapper/gradle-wrapper.jar new file mode 100644 index 0000000..085a1cd Binary files /dev/null and b/VL03-02-01/gradle/wrapper/gradle-wrapper.jar differ diff --git a/VL03-02-01/gradle/wrapper/gradle-wrapper.properties b/VL03-02-01/gradle/wrapper/gradle-wrapper.properties new file mode 100644 index 0000000..f934c8a --- /dev/null +++ b/VL03-02-01/gradle/wrapper/gradle-wrapper.properties @@ -0,0 +1,6 @@ +#Sun Mar 15 22:48:49 CET 2015 +distributionBase=GRADLE_USER_HOME +distributionPath=wrapper/dists +zipStoreBase=GRADLE_USER_HOME +zipStorePath=wrapper/dists +distributionUrl=https\://services.gradle.org/distributions/gradle-8.4-bin.zip diff --git a/VL03-02-01/gradlew b/VL03-02-01/gradlew new file mode 100644 index 0000000..91a7e26 --- /dev/null +++ b/VL03-02-01/gradlew @@ -0,0 +1,164 @@ +#!/usr/bin/env bash + +############################################################################## +## +## Gradle start up script for UN*X +## +############################################################################## + +# Add default JVM options here. You can also use JAVA_OPTS and GRADLE_OPTS to pass JVM options to this script. +DEFAULT_JVM_OPTS="" + +APP_NAME="Gradle" +APP_BASE_NAME=`basename "$0"` + +# Use the maximum available, or set MAX_FD != -1 to use that value. +MAX_FD="maximum" + +warn ( ) { + echo "$*" +} + +die ( ) { + echo + echo "$*" + echo + exit 1 +} + +# OS specific support (must be 'true' or 'false'). +cygwin=false +msys=false +darwin=false +case "`uname`" in + CYGWIN* ) + cygwin=true + ;; + Darwin* ) + darwin=true + ;; + MINGW* ) + msys=true + ;; +esac + +# For Cygwin, ensure paths are in UNIX format before anything is touched. +if $cygwin ; then + [ -n "$JAVA_HOME" ] && JAVA_HOME=`cygpath --unix "$JAVA_HOME"` +fi + +# Attempt to set APP_HOME +# Resolve links: $0 may be a link +PRG="$0" +# Need this for relative symlinks. +while [ -h "$PRG" ] ; do + ls=`ls -ld "$PRG"` + link=`expr "$ls" : '.*-> \(.*\)$'` + if expr "$link" : '/.*' > /dev/null; then + PRG="$link" + else + PRG=`dirname "$PRG"`"/$link" + fi +done +SAVED="`pwd`" +cd "`dirname \"$PRG\"`/" >&- +APP_HOME="`pwd -P`" +cd "$SAVED" >&- + +CLASSPATH=$APP_HOME/gradle/wrapper/gradle-wrapper.jar + +# Determine the Java command to use to start the JVM. +if [ -n "$JAVA_HOME" ] ; then + if [ -x "$JAVA_HOME/jre/sh/java" ] ; then + # IBM's JDK on AIX uses strange locations for the executables + JAVACMD="$JAVA_HOME/jre/sh/java" + else + JAVACMD="$JAVA_HOME/bin/java" + fi + if [ ! -x "$JAVACMD" ] ; then + die "ERROR: JAVA_HOME is set to an invalid directory: $JAVA_HOME + +Please set the JAVA_HOME variable in your environment to match the +location of your Java installation." + fi +else + JAVACMD="java" + which java >/dev/null 2>&1 || die "ERROR: JAVA_HOME is not set and no 'java' command could be found in your PATH. + +Please set the JAVA_HOME variable in your environment to match the +location of your Java installation." +fi + +# Increase the maximum file descriptors if we can. +if [ "$cygwin" = "false" -a "$darwin" = "false" ] ; then + MAX_FD_LIMIT=`ulimit -H -n` + if [ $? -eq 0 ] ; then + if [ "$MAX_FD" = "maximum" -o "$MAX_FD" = "max" ] ; then + MAX_FD="$MAX_FD_LIMIT" + fi + ulimit -n $MAX_FD + if [ $? -ne 0 ] ; then + warn "Could not set maximum file descriptor limit: $MAX_FD" + fi + else + warn "Could not query maximum file descriptor limit: $MAX_FD_LIMIT" + fi +fi + +# For Darwin, add options to specify how the application appears in the dock +if $darwin; then + GRADLE_OPTS="$GRADLE_OPTS \"-Xdock:name=$APP_NAME\" \"-Xdock:icon=$APP_HOME/media/gradle.icns\"" +fi + +# For Cygwin, switch paths to Windows format before running java +if $cygwin ; then + APP_HOME=`cygpath --path --mixed "$APP_HOME"` + CLASSPATH=`cygpath --path --mixed "$CLASSPATH"` + + # We build the pattern for arguments to be converted via cygpath + ROOTDIRSRAW=`find -L / -maxdepth 1 -mindepth 1 -type d 2>/dev/null` + SEP="" + for dir in $ROOTDIRSRAW ; do + ROOTDIRS="$ROOTDIRS$SEP$dir" + SEP="|" + done + OURCYGPATTERN="(^($ROOTDIRS))" + # Add a user-defined pattern to the cygpath arguments + if [ "$GRADLE_CYGPATTERN" != "" ] ; then + OURCYGPATTERN="$OURCYGPATTERN|($GRADLE_CYGPATTERN)" + fi + # Now convert the arguments - kludge to limit ourselves to /bin/sh + i=0 + for arg in "$@" ; do + CHECK=`echo "$arg"|egrep -c "$OURCYGPATTERN" -` + CHECK2=`echo "$arg"|egrep -c "^-"` ### Determine if an option + + if [ $CHECK -ne 0 ] && [ $CHECK2 -eq 0 ] ; then ### Added a condition + eval `echo args$i`=`cygpath --path --ignore --mixed "$arg"` + else + eval `echo args$i`="\"$arg\"" + fi + i=$((i+1)) + done + case $i in + (0) set -- ;; + (1) set -- "$args0" ;; + (2) set -- "$args0" "$args1" ;; + (3) set -- "$args0" "$args1" "$args2" ;; + (4) set -- "$args0" "$args1" "$args2" "$args3" ;; + (5) set -- "$args0" "$args1" "$args2" "$args3" "$args4" ;; + (6) set -- "$args0" "$args1" "$args2" "$args3" "$args4" "$args5" ;; + (7) set -- "$args0" "$args1" "$args2" "$args3" "$args4" "$args5" "$args6" ;; + (8) set -- "$args0" "$args1" "$args2" "$args3" "$args4" "$args5" "$args6" "$args7" ;; + (9) set -- "$args0" "$args1" "$args2" "$args3" "$args4" "$args5" "$args6" "$args7" "$args8" ;; + esac +fi + +# Split up the JVM_OPTS And GRADLE_OPTS values into an array, following the shell quoting and substitution rules +function splitJvmOpts() { + JVM_OPTS=("$@") +} +eval splitJvmOpts $DEFAULT_JVM_OPTS $JAVA_OPTS $GRADLE_OPTS +JVM_OPTS[${#JVM_OPTS[*]}]="-Dorg.gradle.appname=$APP_BASE_NAME" + +exec "$JAVACMD" "${JVM_OPTS[@]}" -classpath "$CLASSPATH" org.gradle.wrapper.GradleWrapperMain "$@" diff --git a/VL03-02-01/gradlew.bat b/VL03-02-01/gradlew.bat new file mode 100644 index 0000000..8a0b282 --- /dev/null +++ b/VL03-02-01/gradlew.bat @@ -0,0 +1,90 @@ +@if "%DEBUG%" == "" @echo off +@rem ########################################################################## +@rem +@rem Gradle startup script for Windows +@rem +@rem ########################################################################## + +@rem Set local scope for the variables with windows NT shell +if "%OS%"=="Windows_NT" setlocal + +@rem Add default JVM options here. You can also use JAVA_OPTS and GRADLE_OPTS to pass JVM options to this script. +set DEFAULT_JVM_OPTS= + +set DIRNAME=%~dp0 +if "%DIRNAME%" == "" set DIRNAME=. +set APP_BASE_NAME=%~n0 +set APP_HOME=%DIRNAME% + +@rem Find java.exe +if defined JAVA_HOME goto findJavaFromJavaHome + +set JAVA_EXE=java.exe +%JAVA_EXE% -version >NUL 2>&1 +if "%ERRORLEVEL%" == "0" goto init + +echo. +echo ERROR: JAVA_HOME is not set and no 'java' command could be found in your PATH. +echo. +echo Please set the JAVA_HOME variable in your environment to match the +echo location of your Java installation. + +goto fail + +:findJavaFromJavaHome +set JAVA_HOME=%JAVA_HOME:"=% +set JAVA_EXE=%JAVA_HOME%/bin/java.exe + +if exist "%JAVA_EXE%" goto init + +echo. +echo ERROR: JAVA_HOME is set to an invalid directory: %JAVA_HOME% +echo. +echo Please set the JAVA_HOME variable in your environment to match the +echo location of your Java installation. + +goto fail + +:init +@rem Get command-line arguments, handling Windowz variants + +if not "%OS%" == "Windows_NT" goto win9xME_args +if "%@eval[2+2]" == "4" goto 4NT_args + +:win9xME_args +@rem Slurp the command line arguments. +set CMD_LINE_ARGS= +set _SKIP=2 + +:win9xME_args_slurp +if "x%~1" == "x" goto execute + +set CMD_LINE_ARGS=%* +goto execute + +:4NT_args +@rem Get arguments from the 4NT Shell from JP Software +set CMD_LINE_ARGS=%$ + +:execute +@rem Setup the command line + +set CLASSPATH=%APP_HOME%\gradle\wrapper\gradle-wrapper.jar + +@rem Execute Gradle +"%JAVA_EXE%" %DEFAULT_JVM_OPTS% %JAVA_OPTS% %GRADLE_OPTS% "-Dorg.gradle.appname=%APP_BASE_NAME%" -classpath "%CLASSPATH%" org.gradle.wrapper.GradleWrapperMain %CMD_LINE_ARGS% + +:end +@rem End local scope for the variables with windows NT shell +if "%ERRORLEVEL%"=="0" goto mainEnd + +:fail +rem Set variable GRADLE_EXIT_CONSOLE if you need the _script_ return code instead of +rem the _cmd.exe /c_ return code! +if not "" == "%GRADLE_EXIT_CONSOLE%" exit 1 +exit /b 1 + +:mainEnd +if "%OS%"=="Windows_NT" endlocal + +:omega diff --git a/VL03-02-01/src/main/java/de/dhbw/parprog/Account.java b/VL03-02-01/src/main/java/de/dhbw/parprog/Account.java new file mode 100644 index 0000000..bb8d8ad --- /dev/null +++ b/VL03-02-01/src/main/java/de/dhbw/parprog/Account.java @@ -0,0 +1,37 @@ +package de.dhbw.parprog; + +/** + * Class which represents a bank account. + */ +public class Account { + + /** + * The lower limit of the balance. + */ + public static final long LOWER_LIMIT = 0; + + /** + * The upper limit of the balance. + */ + public static final long UPPER_LIMIT = 100000; + + /** + * The balance of the bank account. + */ + public long balance = 0; + + /** + * The bank account number. + */ + public long number = 0; + + /** + * Constructor to create a new bank account. + * @param number The bank account number. + * @param balance The initial balance of the bank account. + */ + public Account(long number, long balance) { + this.balance = balance; + this.number = number; + } +} diff --git a/VL03-02-01/src/main/java/de/dhbw/parprog/Bank.java b/VL03-02-01/src/main/java/de/dhbw/parprog/Bank.java new file mode 100644 index 0000000..b4b2bff --- /dev/null +++ b/VL03-02-01/src/main/java/de/dhbw/parprog/Bank.java @@ -0,0 +1,117 @@ +package de.dhbw.parprog; + +/** + * Class which represents a bank. + */ +public class Bank { + + /** + * The next bank account number which can be used for a new bank account. + * This number is used to get distinct bank account numbers. + */ + private static int number = 100000; + + /** + * Creates a new bank account. + * @return A new bank account. + */ + public synchronized Account createAccount() { + return new Account(Bank.number++, 0); + } + + /** + * Gets the current balance of a bank account. + * @param account The bank account to get the balance. + * @return The current balance of the bank account. + * @throws IllegalArgumentException + */ + public long getBalance(Account account) throws IllegalArgumentException { + if (account == null) { + throw new IllegalArgumentException(); + } else { + return account.balance; + } + } + + /** + * Deposits an amount into a bank account. + * @param account The bank account to deposit the amount into. + * @param amount The amount to deposit into the bank account. + * @throws IllegalArgumentException + * @throws IllegalAccountStateException + */ + public void deposit(Account account, long amount) throws IllegalAccountStateException, IllegalArgumentException { + + if (account == null || amount < 0) { + throw new IllegalArgumentException(); + } + + if ((this.getBalance(account) + amount) > Account.UPPER_LIMIT) { + throw new IllegalAccountStateException(); + } else { + account.balance += amount; + } + } + + /** + * Withdraws an amount from a bank account. + * @param account The bank account to withdraw the amount from. + * @param amount The amount to withdraw from the bank account. + * @throws IllegalArgumentException + * @throws IllegalAccountStateException + */ + public void withdraw(Account account, long amount) throws IllegalAccountStateException, IllegalArgumentException { + + if (account == null || amount < 0) { + throw new IllegalArgumentException(); + } + + if ((this.getBalance(account) - amount) < Account.LOWER_LIMIT) { + throw new IllegalAccountStateException(); + } else { + account.balance -= amount; + } + } + + /** + * Transfers a amount between two bank accounts. + * @param fromAccount The bank account to withdraw from. + * @param toAccount The bank account to deposit into. + * @param amount The amount to transfer between the two bank accounts. + * @throws IllegalArgumentException + * @throws IllegalAccountStateException + */ + public void transfer(Account fromAccount, Account toAccount, long amount) throws IllegalAccountStateException, IllegalArgumentException { + + if (fromAccount == null || toAccount == null || amount < 0) { + throw new IllegalArgumentException(); + } + + Account a, b; + + // it is important to lock the accounts always in the same order. + // the bank account number is used to sort the bank accounts. + if (fromAccount.number > toAccount.number) { + a = fromAccount; + b = toAccount; + } else { + a = toAccount; + b = fromAccount; + } + + // lock the two bank accounts to transfer the amount between them. + // a different thread should not be able to do changes while the transfer is running. + synchronized(a) { + synchronized(b) { + if ((this.getBalance(fromAccount) - amount) < Account.LOWER_LIMIT) { + throw new IllegalAccountStateException(); + } + if ((this.getBalance(toAccount) + amount) > Account.UPPER_LIMIT) { + throw new IllegalAccountStateException(); + } + this.deposit(fromAccount, amount); + this.withdraw(toAccount, amount); + } + } + } +} diff --git a/VL03-02-01/src/main/java/de/dhbw/parprog/Example.java b/VL03-02-01/src/main/java/de/dhbw/parprog/Example.java new file mode 100644 index 0000000..35dcb80 --- /dev/null +++ b/VL03-02-01/src/main/java/de/dhbw/parprog/Example.java @@ -0,0 +1,37 @@ +package de.dhbw.parprog; + +/** + * Class which represents an example / demo. + */ +public class Example { + public static void main(String[] args) { + + // initialize the bank and two bank accounts with initial balance. + Bank bank = new Bank(); + Account a = bank.createAccount(); + Account b = bank.createAccount(); + bank.deposit(a, 10000); + bank.deposit(b, 10000); + + // output the balance of the bank accounts before running some transfers. + System.out.println("Account A=" + a.number + ", Account B=" + b.number); + System.out.println("Start Balance: A=" + bank.getBalance(a) + ", B=" + bank.getBalance(b)); + + // create and start two threads transfering an amount between the two bank accounts. + Thread t1 = new Thread(new Transfer(bank, a, b, 10, 1000)); + Thread t2 = new Thread(new Transfer(bank, b, a, 10, 1000)); + t1.start(); + t2.start(); + + // wait until the threads are finished. + try { + t1.join(); + t2.join(); + } catch (InterruptedException e) { + e.printStackTrace(); + } + + // output the balance of the bank accounts after finishing the transfers. + System.out.println("End Balance: A=" + bank.getBalance(a) + ", B=" + bank.getBalance(b)); + } +} diff --git a/VL03-02-01/src/main/java/de/dhbw/parprog/IllegalAccountStateException.java b/VL03-02-01/src/main/java/de/dhbw/parprog/IllegalAccountStateException.java new file mode 100644 index 0000000..79eb7a5 --- /dev/null +++ b/VL03-02-01/src/main/java/de/dhbw/parprog/IllegalAccountStateException.java @@ -0,0 +1,5 @@ +package de.dhbw.parprog; + +public class IllegalAccountStateException extends RuntimeException { + +} diff --git a/VL03-02-01/src/main/java/de/dhbw/parprog/Transfer.java b/VL03-02-01/src/main/java/de/dhbw/parprog/Transfer.java new file mode 100644 index 0000000..f0005b8 --- /dev/null +++ b/VL03-02-01/src/main/java/de/dhbw/parprog/Transfer.java @@ -0,0 +1,57 @@ +package de.dhbw.parprog; + +/** + * Class which represents a transfer between two bank accounts. + */ +public class Transfer implements Runnable { + + /** + * The bank of the two bank accounts. + */ + Bank bank; + + /** + * The bank account to transfer from. + */ + Account fromAccount; + + /** + * The bank account to transfer into. + */ + Account toAccount; + + /** + * The amount to transfer between the two bank accounts. + */ + long amount; + + /** + * The number of transfers between the two bank accounts. + */ + int count; + + /** + * Constructor to create a new transfer between two bank accounts. + * @param bank The bank of the bank accounts. + * @param fromAccount The bank account to transfer from. + * @param toAccount The bank account to transfer into. + * @param amount The amount to transfer between the two bank accounts. + * @param count The number of transfers between the two bank acocunts. + */ + Transfer(Bank bank, Account fromAccount, Account toAccount, long amount, int count) { + this.bank = bank; + this.fromAccount = fromAccount; + this.toAccount = toAccount; + this.amount = amount; + this.count = count; + } + + /** + * The method to do the multiple transfers with a given amount. + */ + public void run() { + for (int i = 0; i < this.count; i++) { + this.bank.transfer(this.fromAccount, this.toAccount, this.amount); + } + } +} diff --git a/VL03-02-01/src/test/java/de/dhbw/parprog/AccountStateTests.java b/VL03-02-01/src/test/java/de/dhbw/parprog/AccountStateTests.java new file mode 100644 index 0000000..464933a --- /dev/null +++ b/VL03-02-01/src/test/java/de/dhbw/parprog/AccountStateTests.java @@ -0,0 +1,55 @@ +package de.dhbw.parprog; + +import static org.fest.assertions.Assertions.assertThat; + +import org.junit.Assert; +import org.junit.Before; +import org.junit.Rule; +import org.junit.Test; +import org.junit.rules.ExpectedException; +import org.junit.runner.RunWith; +import org.junit.runners.JUnit4; + + +@RunWith(JUnit4.class) +public class AccountStateTests { + Bank bank; + + @Rule + public ExpectedException thrown = ExpectedException.none(); + + @Before + public void setupTest() { + bank = new Bank(); + } + + @Test + public void newAccountHasNoCredits() { + Account a = bank.createAccount(); + assertThat(bank.getBalance(a)).isEqualTo(0); + } + + @Test + public void canDepositAndWithdraw() throws IllegalAccountStateException { + Account a = bank.createAccount(); + bank.deposit(a, 10); + bank.withdraw(a, 5); + } + + @Test + public void cantDepositMoreThanMaximum() throws IllegalAccountStateException { + Account a = bank.createAccount(); + bank.deposit(a, Account.UPPER_LIMIT); + thrown.expect(IllegalAccountStateException.class); + bank.deposit(a, 1); + Assert.fail("Should have caused an exception"); + } + + @Test + public void cantWithdrawBelowMinimum() throws IllegalAccountStateException { + Account a = bank.createAccount(); + thrown.expect(IllegalAccountStateException.class); + bank.withdraw(a, 1); + Assert.fail("Should have caused an exception"); + } +}