started implementing my own arraylist then saw everyone else just using arraylist... so i did that in 10 seconds and i'm done

Checkbook/.idea/compiler.xml

@@ -0,0 +1,16 @@
+<?xml version="1.0" encoding="UTF-8"?>
+<project version="4">
+  <component name="CompilerConfiguration">
+    <annotationProcessing>
+      <profile name="Maven default annotation processors profile" enabled="true">
+        <sourceOutputDir name="target/generated-sources/annotations" />
+        <sourceTestOutputDir name="target/generated-test-sources/test-annotations" />
+        <outputRelativeToContentRoot value="true" />
+        <module name="Checkbook" />
+      </profile>
+    </annotationProcessing>
+    <bytecodeTargetLevel>
+      <module name="Checkbook" target="1.8" />
+    </bytecodeTargetLevel>
+  </component>
+</project>

Checkbook/.idea/encodings.xml

@@ -0,0 +1,4 @@
+<?xml version="1.0" encoding="UTF-8"?>
+<project version="4">
+  <component name="Encoding" addBOMForNewFiles="with NO BOM" />
+</project>

Checkbook/.idea/libraries/Maven__junit_junit_4_0.xml

@@ -0,0 +1,13 @@
+<component name="libraryTable">
+  <library name="Maven: junit:junit:4.0">
+    <CLASSES>
+      <root url="jar://$MAVEN_REPOSITORY$/junit/junit/4.0/junit-4.0.jar!/" />
+    </CLASSES>
+    <JAVADOC>
+      <root url="jar://$MAVEN_REPOSITORY$/junit/junit/4.0/junit-4.0-javadoc.jar!/" />
+    </JAVADOC>
+    <SOURCES>
+      <root url="jar://$MAVEN_REPOSITORY$/junit/junit/4.0/junit-4.0-sources.jar!/" />
+    </SOURCES>
+  </library>
+</component>

Checkbook/.idea/misc.xml

@@ -0,0 +1,13 @@
+<?xml version="1.0" encoding="UTF-8"?>
+<project version="4">
+  <component name="MavenProjectsManager">
+    <option name="originalFiles">
+      <list>
+        <option value="$PROJECT_DIR$/pom.xml" />
+      </list>
+    </option>
+  </component>
+  <component name="ProjectRootManager" version="2" languageLevel="JDK_1_8" project-jdk-name="1.8" project-jdk-type="JavaSDK">
+    <output url="file://$PROJECT_DIR$/classes" />
+  </component>
+</project>

Checkbook/.idea/modules.xml

@@ -0,0 +1,8 @@
+<?xml version="1.0" encoding="UTF-8"?>
+<project version="4">
+  <component name="ProjectModuleManager">
+    <modules>
+      <module fileurl="file://$PROJECT_DIR$/Checkbook.iml" filepath="$PROJECT_DIR$/Checkbook.iml" />
+    </modules>
+  </component>
+</project>

Checkbook/.idea/vcs.xml

@@ -0,0 +1,6 @@
+<?xml version="1.0" encoding="UTF-8"?>
+<project version="4">
+  <component name="VcsDirectoryMappings">
+    <mapping directory="$PROJECT_DIR$/.." vcs="Git" />
+  </component>
+</project>

Checkbook/.idea/workspace.xml

@@ -0,0 +1,343 @@
+<?xml version="1.0" encoding="UTF-8"?>
+<project version="4">
+  <component name="ChangeListManager">
+    <list default="true" id="86bea83e-ff28-4c08-8563-407f3ac4c927" name="Default Changelist" comment="">
+      <change beforePath="$PROJECT_DIR$/Checkbook.iml" beforeDir="false" />
+      <change beforePath="$PROJECT_DIR$/src/main/java/AccountBook.java" beforeDir="false" afterPath="$PROJECT_DIR$/src/main/java/AccountBook.java" afterDir="false" />
+      <change beforePath="$PROJECT_DIR$/src/main/java/Checkbook.java" beforeDir="false" afterPath="$PROJECT_DIR$/src/main/java/Checkbook.java" afterDir="false" />
+      <change beforePath="$PROJECT_DIR$/src/main/java/Transaction.java" beforeDir="false" afterPath="$PROJECT_DIR$/src/main/java/Transaction.java" afterDir="false" />
+      <change beforePath="$PROJECT_DIR$/src/test/java/CheckbookTest.java" beforeDir="false" afterPath="$PROJECT_DIR$/src/test/java/CheckbookTest.java" afterDir="false" />
+    </list>
+    <ignored path="$PROJECT_DIR$/target/" />
+    <option name="EXCLUDED_CONVERTED_TO_IGNORED" value="true" />
+    <option name="SHOW_DIALOG" value="false" />
+    <option name="HIGHLIGHT_CONFLICTS" value="true" />
+    <option name="HIGHLIGHT_NON_ACTIVE_CHANGELIST" value="false" />
+    <option name="LAST_RESOLUTION" value="IGNORE" />
+  </component>
+  <component name="FileEditorManager">
+    <leaf>
+      <file pinned="false" current-in-tab="false">
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+      </file>
+      <file pinned="false" current-in-tab="true">
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+              </folding>
+            </state>
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+        </entry>
+      </file>
+      <file pinned="false" current-in-tab="false">
+        <entry file="jar:///Library/Java/JavaVirtualMachines/jdk1.8.0_191.jdk/Contents/Home/src.zip!/java/util/ArrayList.java">
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+          </provider>
+        </entry>
+      </file>
+      <file pinned="false" current-in-tab="false">
+        <entry file="file://$PROJECT_DIR$/src/main/java/GenericAccount.java">
+          <provider selected="true" editor-type-id="text-editor">
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+      </file>
+      <file pinned="false" current-in-tab="false">
+        <entry file="jar:///Library/Java/JavaVirtualMachines/jdk1.8.0_191.jdk/Contents/Home/src.zip!/java/util/Collection.java">
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+            </state>
+          </provider>
+        </entry>
+      </file>
+    </leaf>
+  </component>
+  <component name="FindInProjectRecents">
+    <findStrings>
+      <find>public</find>
+      <find>Student</find>
+      <find>toArray</find>
+      <find>remove</find>
+      <find>contains</find>
+      <find>retain</find>
+    </findStrings>
+  </component>
+  <component name="Git.Settings">
+    <option name="RECENT_GIT_ROOT_PATH" value="$PROJECT_DIR$/.." />
+    <option name="RECENT_BRANCH_BY_REPOSITORY">
+      <map>
+        <entry key="$PROJECT_DIR$/.." value="master" />
+      </map>
+    </option>
+  </component>
+  <component name="IdeDocumentHistory">
+    <option name="CHANGED_PATHS">
+      <list>
+        <option value="$PROJECT_DIR$/src/main/java/Transaction.java" />
+        <option value="$PROJECT_DIR$/src/main/java/AccountBook.java" />
+        <option value="$PROJECT_DIR$/src/test/java/CheckbookTest.java" />
+        <option value="$PROJECT_DIR$/src/main/java/Checkbook.java" />
+      </list>
+    </option>
+  </component>
+  <component name="ProjectFrameBounds" extendedState="6" fullScreen="true">
+    <option name="width" value="1440" />
+    <option name="height" value="900" />
+  </component>
+  <component name="ProjectLevelVcsManager" settingsEditedManually="true" />
+  <component name="ProjectView">
+    <navigator proportions="" version="1">
+      <foldersAlwaysOnTop value="true" />
+    </navigator>
+    <panes>
+      <pane id="PackagesPane" />
+      <pane id="Scope" />
+      <pane id="ProjectPane">
+        <subPane>
+          <expand>
+            <path>
+              <item name="Checkbook" type="b2602c69:ProjectViewProjectNode" />
+              <item name="Checkbook" type="462c0819:PsiDirectoryNode" />
+            </path>
+            <path>
+              <item name="Checkbook" type="b2602c69:ProjectViewProjectNode" />
+              <item name="Checkbook" type="462c0819:PsiDirectoryNode" />
+              <item name="src" type="462c0819:PsiDirectoryNode" />
+            </path>
+            <path>
+              <item name="Checkbook" type="b2602c69:ProjectViewProjectNode" />
+              <item name="Checkbook" type="462c0819:PsiDirectoryNode" />
+              <item name="src" type="462c0819:PsiDirectoryNode" />
+              <item name="main" type="462c0819:PsiDirectoryNode" />
+            </path>
+            <path>
+              <item name="Checkbook" type="b2602c69:ProjectViewProjectNode" />
+              <item name="Checkbook" type="462c0819:PsiDirectoryNode" />
+              <item name="src" type="462c0819:PsiDirectoryNode" />
+              <item name="main" type="462c0819:PsiDirectoryNode" />
+              <item name="java" type="462c0819:PsiDirectoryNode" />
+            </path>
+            <path>
+              <item name="Checkbook" type="b2602c69:ProjectViewProjectNode" />
+              <item name="Checkbook" type="462c0819:PsiDirectoryNode" />
+              <item name="src" type="462c0819:PsiDirectoryNode" />
+              <item name="test" type="462c0819:PsiDirectoryNode" />
+            </path>
+            <path>
+              <item name="Checkbook" type="b2602c69:ProjectViewProjectNode" />
+              <item name="Checkbook" type="462c0819:PsiDirectoryNode" />
+              <item name="src" type="462c0819:PsiDirectoryNode" />
+              <item name="test" type="462c0819:PsiDirectoryNode" />
+              <item name="java" type="462c0819:PsiDirectoryNode" />
+            </path>
+          </expand>
+          <select />
+        </subPane>
+      </pane>
+    </panes>
+  </component>
+  <component name="PropertiesComponent">
+    <property name="WebServerToolWindowFactoryState" value="false" />
+    <property name="aspect.path.notification.shown" value="true" />
+    <property name="com.android.tools.idea.instantapp.provision.ProvisionBeforeRunTaskProvider.myTimeStamp" value="1544213381725" />
+    <property name="com.intellij.testIntegration.createTest.CreateTestDialog.defaultLibrary" value="JUnit4" />
+    <property name="com.intellij.testIntegration.createTest.CreateTestDialog.defaultLibrarySuperClass.JUnit4" value="" />
+    <property name="extract.method.default.visibility" value="private" />
+    <property name="nodejs_interpreter_path.stuck_in_default_project" value="undefined stuck path" />
+    <property name="nodejs_npm_path_reset_for_default_project" value="true" />
+  </component>
+  <component name="RecentsManager">
+    <key name="CreateTestDialog.RecentsKey">
+      <recent name="" />
+    </key>
+    <key name="CreateTestDialog.Recents.Supers">
+      <recent name="" />
+    </key>
+  </component>
+  <component name="RunDashboard">
+    <option name="ruleStates">
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+          <option name="name" value="ConfigurationTypeDashboardGroupingRule" />
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+          <option name="name" value="StatusDashboardGroupingRule" />
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+  </component>
+  <component name="SvnConfiguration">
+    <configuration />
+  </component>
+  <component name="TaskManager">
+    <task active="true" id="Default" summary="Default task">
+      <changelist id="86bea83e-ff28-4c08-8563-407f3ac4c927" name="Default Changelist" comment="" />
+      <created>1544199126934</created>
+      <option name="number" value="Default" />
+      <option name="presentableId" value="Default" />
+      <updated>1544199126934</updated>
+      <workItem from="1544199128297" duration="10136000" />
+    </task>
+    <servers />
+  </component>
+  <component name="TimeTrackingManager">
+    <option name="totallyTimeSpent" value="10136000" />
+  </component>
+  <component name="ToolWindowManager">
+    <frame x="0" y="0" width="904" height="900" extended-state="6" />
+    <editor active="true" />
+    <layout>
+      <window_info id="Favorites" side_tool="true" />
+      <window_info id="Image Layers" />
+      <window_info id="Designer" />
+      <window_info id="UI Designer" />
+      <window_info id="Capture Tool" />
+      <window_info id="Learn" />
+      <window_info active="true" content_ui="combo" id="Project" order="0" visible="true" weight="0.26218098" />
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+      <window_info anchor="bottom" id="Docker" show_stripe_button="false" />
+      <window_info anchor="bottom" id="Version Control" />
+      <window_info anchor="bottom" id="Terminal" />
+      <window_info anchor="bottom" id="Event Log" side_tool="true" />
+      <window_info anchor="bottom" id="Database Changes" />
+      <window_info anchor="bottom" id="Message" order="0" />
+      <window_info anchor="bottom" id="Find" order="1" />
+      <window_info anchor="bottom" id="Run" order="2" />
+      <window_info anchor="bottom" id="Debug" order="3" weight="0.4" />
+      <window_info anchor="bottom" id="Cvs" order="4" weight="0.25" />
+      <window_info anchor="bottom" id="Inspection" order="5" weight="0.4" />
+      <window_info anchor="bottom" id="TODO" order="6" />
+      <window_info anchor="right" id="Palette" />
+      <window_info anchor="right" id="Theme Preview" />
+      <window_info anchor="right" id="Maven" />
+      <window_info anchor="right" id="Capture Analysis" />
+      <window_info anchor="right" id="Palette&#9;" />
+      <window_info anchor="right" id="Database" />
+      <window_info anchor="right" id="Commander" internal_type="SLIDING" order="0" type="SLIDING" weight="0.4" />
+      <window_info anchor="right" id="Ant Build" order="1" weight="0.25" />
+      <window_info anchor="right" content_ui="combo" id="Hierarchy" order="2" weight="0.25" />
+    </layout>
+  </component>
+  <component name="TypeScriptGeneratedFilesManager">
+    <option name="version" value="1" />
+  </component>
+  <component name="editorHistoryManager">
+    <entry file="jar:///Library/Java/JavaVirtualMachines/jdk1.8.0_191.jdk/Contents/Home/src.zip!/java/util/Collection.java">
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+    </entry>
+    <entry file="file://$PROJECT_DIR$/src/main/java/AccountBook.java">
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+    </entry>
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+        </state>
+      </provider>
+    </entry>
+    <entry file="file://$PROJECT_DIR$/src/main/java/Payee.java">
+      <provider selected="true" editor-type-id="text-editor">
+        <state>
+          <caret column="13" selection-start-column="13" selection-end-column="13" />
+        </state>
+      </provider>
+    </entry>
+    <entry file="file://$PROJECT_DIR$/src/main/java/TransactionType.java">
+      <provider selected="true" editor-type-id="text-editor">
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+        </state>
+      </provider>
+    </entry>
+    <entry file="file://$PROJECT_DIR$/src/test/java/CheckbookTest.java">
+      <provider selected="true" editor-type-id="text-editor">
+        <state relative-caret-position="593">
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+        </state>
+      </provider>
+    </entry>
+    <entry file="file://$PROJECT_DIR$/src/main/java/GenericAccount.java">
+      <provider selected="true" editor-type-id="text-editor">
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+          <caret line="1" column="13" selection-start-line="1" selection-start-column="13" selection-end-line="1" selection-end-column="13" />
+        </state>
+      </provider>
+    </entry>
+    <entry file="jar:///Library/Java/JavaVirtualMachines/jdk1.8.0_191.jdk/Contents/Home/src.zip!/java/util/ArrayList.java">
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+      </provider>
+    </entry>
+    <entry file="file://$PROJECT_DIR$/src/main/java/Checkbook.java">
+      <provider selected="true" editor-type-id="text-editor">
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+            <element signature="e#276#277#0" expanded="true" />
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+          </folding>
+        </state>
+      </provider>
+    </entry>
+  </component>
+</project>

Checkbook/Checkbook.iml

@@ -5,11 +5,10 @@
     <output-test url="file://$MODULE_DIR$/target/test-classes" />
     <content url="file://$MODULE_DIR$">
       <sourceFolder url="file://$MODULE_DIR$/src/main/java" isTestSource="false" />
-      <sourceFolder url="file://$MODULE_DIR$/src/main/resources" type="java-resource" />
       <sourceFolder url="file://$MODULE_DIR$/src/test/java" isTestSource="true" />
       <excludeFolder url="file://$MODULE_DIR$/target" />
     </content>
-    <orderEntry type="jdk" jdkName="1.8" jdkType="JavaSDK" />
+    <orderEntry type="inheritedJdk" />
     <orderEntry type="sourceFolder" forTests="false" />
     <orderEntry type="library" name="Maven: junit:junit:4.0" level="project" />
   </component>

Checkbook/src/main/java/AccountBook.java

@@ -1,12 +1,12 @@
 import java.time.LocalDate;
 
-public interface AccountBook {
-    public Integer getId();
-    public LocalDate getDate();
-    public TransactionType getType();
-    public String getMemo() ;
-    public void setMemo(String memo);
-    public Payee getPayee();
-    public void setPayee(Payee payee);
-    public Double getAmount();
+interface AccountBook {
+    Integer getId();
+    LocalDate getDate();
+    TransactionType getType();
+    String getMemo() ;
+    void setMemo(String memo);
+    Payee getPayee();
+    void setPayee(Payee payee);
+    Double getAmount();
 }

Checkbook/src/main/java/Checkbook.java

@@ -1,4 +1,92 @@
-public class Checkbook {
+import java.util.*;
+
+public class Checkbook<T extends Transaction> implements Collection<T> {
+    private ArrayList<Transaction> transactions;
+    private final int CHECKBOOK_SIZE = 100;
+
+    private Payee owner;
+    private double cashAmount;
+
+    public Checkbook() {
+        this.transactions = new ArrayList<>();
+    }
+
+    public Checkbook(double cashAmount) {
+        this();
+        this.cashAmount = cashAmount;
+    }
+
+    public Checkbook(Payee owner, double cashAmount) {
+        this(cashAmount);
+        this.owner = owner;
+    }
+
+    @Override
+    public int size() {
+        return transactions.size();
+    }
+
+    @Override
+    public boolean isEmpty() {
+        return transactions.isEmpty();
+    }
+
+    @Override
+    public boolean contains(Object t) {
+        return transactions.contains(t);
+    }
+
+    @Override
+    public Iterator<T> iterator() {
+        return (Iterator<T>) transactions.iterator();
+    }
+
+    @Override
+    public Transaction[] toArray() {
+        return (Transaction[]) transactions.toArray();
+    }
+
+    @Override
+    public <T> T[] toArray(T[] a) {
+        return transactions.toArray(a);
+    }
+
+    @Override
+    public boolean add(Transaction transaction) {
+        if (size() <= CHECKBOOK_SIZE) { return transactions.add(transaction); }
+        else throw new IndexOutOfBoundsException("Check limit exceeded. You need a new checkbook!");
+    }
+
+    @Override
+    public boolean remove(Object o) {
+        return transactions.remove(o);
+    }
+
+    @Override
+    public boolean containsAll(Collection<?> c) {
+        return transactions.containsAll(c);
+    }
+
+    @Override
+    public boolean addAll(Collection<? extends T> c) {
+        if (size() + c.size() <= CHECKBOOK_SIZE) { return transactions.addAll(c); }
+        else throw new IndexOutOfBoundsException("You do not have enough checks available in your checkbook.");
+    }
+
+    @Override
+    public boolean removeAll(Collection<?> c) {
+        return transactions.removeAll(c);
+    }
+
+    @Override
+    public boolean retainAll(Collection<?> c) {
+        return transactions.retainAll(c);
+    }
+
+    @Override
+    public void clear() {
+        transactions.clear();
+    }
 
     //blind us with your Java eloquence....
 

Checkbook/src/main/java/GenericAccount.java

@@ -1,3 +1,3 @@
 
-public class GenericAccount {
+public class GenericAccount<A extends AccountBook> {
 }

Checkbook/src/main/java/Transaction.java

@@ -6,11 +6,11 @@ public class Transaction {
     private final AtomicReference<LocalDate> date = new AtomicReference<LocalDate>();
     private String memo;
     private Payee payee;
-    private TransactionType typee; // Credit (reduces the checkbook), Debit (increases the checkbook)
+    private TransactionType type; // Credit (reduces the checkbook), Debit (increases the checkbook)
     private Double amount;
 
-    public Transaction(String memo, Payee payee, TransactionType typee, Double amount) {
-        this.typee = typee;
+    public Transaction(String memo, Payee payee, TransactionType type, Double amount) {
+        this.type = type;
         this.memo = memo;
         this.payee = payee;
         this.amount = amount;
@@ -25,7 +25,7 @@ public class Transaction {
     }
 
     public TransactionType getType() {
-        return typee;
+        return type;
     }
 
     public String getMemo() {
@@ -45,7 +45,7 @@ public class Transaction {
     }
 
     public Double getAmount() {
-        if (this.typee == TransactionType.DEBIT) {
+        if (this.type == TransactionType.DEBIT) {
             return amount;
         }
         return (-1.0 * amount);

Checkbook/src/test/java/CheckbookTest.java

@@ -1,3 +1,5 @@
+import org.junit.Test;
+
 import static org.junit.Assert.*;
 
 public class CheckbookTest {
@@ -9,4 +11,56 @@ public class CheckbookTest {
     @org.junit.After
     public void tearDown() throws Exception {
     }
+
+    @Test
+    public void size() {
+    }
+
+    @Test
+    public void isEmpty() {
+    }
+
+    @Test
+    public void contains() {
+    }
+
+    @Test
+    public void iterator() {
+    }
+
+    @Test
+    public void toArray() {
+    }
+
+    @Test
+    public void toArray1() {
+    }
+
+    @Test
+    public void add() {
+    }
+
+    @Test
+    public void remove() {
+    }
+
+    @Test
+    public void containsAll() {
+    }
+
+    @Test
+    public void addAll() {
+    }
+
+    @Test
+    public void removeAll() {
+    }
+
+    @Test
+    public void retainAll() {
+    }
+
+    @Test
+    public void clear() {
+    }
 }