diff --git a/.idea/compiler.xml b/.idea/compiler.xml
new file mode 100644
index 0000000000000000000000000000000000000000..d1120094d9ec720a6c591261358a49402f999e0b
--- /dev/null
+++ b/.idea/compiler.xml
@@ -0,0 +1,13 @@
+<?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="test-oop" />
+      </profile>
+    </annotationProcessing>
+  </component>
+</project>
\ No newline at end of file
diff --git a/.idea/jarRepositories.xml b/.idea/jarRepositories.xml
new file mode 100644
index 0000000000000000000000000000000000000000..712ab9d985c20018a0c97b93d2148ac1ffe588a5
--- /dev/null
+++ b/.idea/jarRepositories.xml
@@ -0,0 +1,20 @@
+<?xml version="1.0" encoding="UTF-8"?>
+<project version="4">
+  <component name="RemoteRepositoriesConfiguration">
+    <remote-repository>
+      <option name="id" value="central" />
+      <option name="name" value="Central Repository" />
+      <option name="url" value="https://repo.maven.apache.org/maven2" />
+    </remote-repository>
+    <remote-repository>
+      <option name="id" value="central" />
+      <option name="name" value="Maven Central repository" />
+      <option name="url" value="https://repo1.maven.org/maven2" />
+    </remote-repository>
+    <remote-repository>
+      <option name="id" value="jboss.community" />
+      <option name="name" value="JBoss Community repository" />
+      <option name="url" value="https://repository.jboss.org/nexus/content/repositories/public/" />
+    </remote-repository>
+  </component>
+</project>
\ No newline at end of file
diff --git a/.idea/misc.xml b/.idea/misc.xml
new file mode 100644
index 0000000000000000000000000000000000000000..9e0563eb9cc6f1fa3fa4ad712e7e2d9bd216735d
--- /dev/null
+++ b/.idea/misc.xml
@@ -0,0 +1,12 @@
+<?xml version="1.0" encoding="UTF-8"?>
+<project version="4">
+  <component name="ExternalStorageConfigurationManager" enabled="true" />
+  <component name="MavenProjectsManager">
+    <option name="originalFiles">
+      <list>
+        <option value="$PROJECT_DIR$/pom.xml" />
+      </list>
+    </option>
+  </component>
+  <component name="ProjectRootManager" version="2" languageLevel="JDK_22" default="true" project-jdk-name="22" project-jdk-type="JavaSDK" />
+</project>
\ No newline at end of file
diff --git a/.idea/workspace.xml b/.idea/workspace.xml
index 0c6b7f84dfde2bd64b22d1c90b432e8ba70231de..5a39b6226143dd3c68c376b1e3361d32b4cc3760 100644
--- a/.idea/workspace.xml
+++ b/.idea/workspace.xml
@@ -1,5 +1,8 @@
 <?xml version="1.0" encoding="UTF-8"?>
 <project version="4">
+  <component name="AutoImportSettings">
+    <option name="autoReloadType" value="SELECTIVE" />
+  </component>
   <component name="BranchesTreeState">
     <expand>
       <path>
@@ -11,7 +14,14 @@
   </component>
   <component name="ChangeListManager">
     <list default="true" id="341e3750-b003-48d6-9720-3813c2a42bbe" name="Default Changelist" comment="">
-      <change beforePath="$PROJECT_DIR$/README.md" beforeDir="false" afterPath="$PROJECT_DIR$/README.md" afterDir="false" />
+      <change afterPath="$PROJECT_DIR$/src/main/java/cn/zust/edu/cn/Circle.java" afterDir="false" />
+      <change afterPath="$PROJECT_DIR$/src/main/java/cn/zust/edu/cn/IShape.java" afterDir="false" />
+      <change afterPath="$PROJECT_DIR$/src/main/java/cn/zust/edu/cn/ShapeManager.java" afterDir="false" />
+      <change afterPath="$PROJECT_DIR$/src/main/java/cn/zust/edu/cn/Triangle.java" afterDir="false" />
+      <change beforePath="$PROJECT_DIR$/.idea/workspace.xml" beforeDir="false" afterPath="$PROJECT_DIR$/.idea/workspace.xml" afterDir="false" />
+      <change beforePath="$PROJECT_DIR$/src/main/java/cn/zust/edu/cn/App.java" beforeDir="false" afterPath="$PROJECT_DIR$/src/main/java/cn/zust/edu/cn/App.java" afterDir="false" />
+      <change beforePath="$PROJECT_DIR$/src/main/java/cn/zust/edu/cn/Point.java" beforeDir="false" afterPath="$PROJECT_DIR$/src/main/java/cn/zust/edu/cn/Point.java" afterDir="false" />
+      <change beforePath="$PROJECT_DIR$/src/main/java/cn/zust/edu/cn/Rectangle.java" beforeDir="false" afterPath="$PROJECT_DIR$/src/main/java/cn/zust/edu/cn/Rectangle.java" afterDir="false" />
     </list>
     <option name="SHOW_DIALOG" value="false" />
     <option name="HIGHLIGHT_CONFLICTS" value="true" />
@@ -21,6 +31,7 @@
   <component name="FileTemplateManagerImpl">
     <option name="RECENT_TEMPLATES">
       <list>
+        <option value="Interface" />
         <option value="Class" />
       </list>
     </option>
@@ -31,26 +42,37 @@
   <component name="MavenImportPreferences">
     <option name="generalSettings">
       <MavenGeneralSettings>
-        <option name="mavenHome" value="D:/software/maven363" />
+        <option name="customMavenHome" value="$PROJECT_DIR$/../../../../software/maven363" />
+        <option name="mavenHomeTypeForPersistence" value="CUSTOM" />
         <option name="userSettingsFile" value="D:\software\maven363\conf\settings.xml" />
       </MavenGeneralSettings>
     </option>
   </component>
+  <component name="ProjectColorInfo"><![CDATA[{
+  "associatedIndex": 0
+}]]></component>
   <component name="ProjectId" id="2EQFlls0QmfIocWyIt5ZbRCr04s" />
   <component name="ProjectLevelVcsManager" settingsEditedManually="true" />
   <component name="ProjectViewState">
     <option name="hideEmptyMiddlePackages" value="true" />
     <option name="showLibraryContents" value="true" />
   </component>
-  <component name="PropertiesComponent">
-    <property name="RunOnceActivity.OpenProjectViewOnStart" value="true" />
-    <property name="RunOnceActivity.ShowReadmeOnStart" value="true" />
-    <property name="SHARE_PROJECT_CONFIGURATION_FILES" value="true" />
-    <property name="WebServerToolWindowFactoryState" value="false" />
-    <property name="aspect.path.notification.shown" value="true" />
-    <property name="nodejs_package_manager_path" value="npm" />
-    <property name="settings.editor.selected.configurable" value="MavenSettings" />
-  </component>
+  <component name="PropertiesComponent"><![CDATA[{
+  "keyToString": {
+    "RunOnceActivity.ShowReadmeOnStart": "true",
+    "RunOnceActivity.git.unshallow": "true",
+    "git-widget-placeholder": "master",
+    "kotlin-language-version-configured": "true",
+    "last_opened_file_path": "D:/wenjian/stepsave/java ee/javaee-test-oop",
+    "node.js.detected.package.eslint": "true",
+    "node.js.detected.package.tslint": "true",
+    "node.js.selected.package.eslint": "(autodetect)",
+    "node.js.selected.package.tslint": "(autodetect)",
+    "nodejs_package_manager_path": "npm",
+    "vue.rearranger.settings.migration": "true",
+    "应用程序.App.executor": "Run"
+  }
+}]]></component>
   <component name="RunManager">
     <configuration name="App" type="Application" factoryName="Application" temporary="true" nameIsGenerated="true">
       <option name="MAIN_CLASS_NAME" value="cn.zust.edu.cn.App" />
@@ -67,10 +89,19 @@
     </configuration>
     <recent_temporary>
       <list>
-        <item itemvalue="Application.App" />
+        <item itemvalue="应用程序.App" />
       </list>
     </recent_temporary>
   </component>
+  <component name="SharedIndexes">
+    <attachedChunks>
+      <set>
+        <option value="bundled-jdk-9823dce3aa75-125ca727e0f0-intellij.indexing.shared.core-IU-243.23654.189" />
+        <option value="bundled-js-predefined-d6986cc7102b-822845ee3bb5-JavaScript-IU-243.23654.189" />
+      </set>
+    </attachedChunks>
+  </component>
+  <component name="SpellCheckerSettings" RuntimeDictionaries="0" Folders="0" CustomDictionaries="0" DefaultDictionary="应用程序级" UseSingleDictionary="true" transferred="true" />
   <component name="SvnConfiguration">
     <configuration />
   </component>
@@ -82,6 +113,7 @@
       <option name="presentableId" value="Default" />
       <updated>1662520054313</updated>
       <workItem from="1662520060171" duration="1981000" />
+      <workItem from="1740905262707" duration="1133000" />
     </task>
     <task id="LOCAL-00001" summary="init">
       <created>1662520558309</created>
@@ -101,7 +133,7 @@
     <servers />
   </component>
   <component name="TypeScriptGeneratedFilesManager">
-    <option name="version" value="2" />
+    <option name="version" value="3" />
   </component>
   <component name="Vcs.Log.Tabs.Properties">
     <option name="TAB_STATES">
diff --git a/src/main/java/cn/zust/edu/cn/App.java b/src/main/java/cn/zust/edu/cn/App.java
index bf9c122443f372c99495cef0daf5d07e13abdff6..d157ffb0a08f27706820a6231f535a2c47721f76 100644
--- a/src/main/java/cn/zust/edu/cn/App.java
+++ b/src/main/java/cn/zust/edu/cn/App.java
@@ -6,7 +6,16 @@ package cn.zust.edu.cn;
  */
 public class App {
     public static void main(String[] args) {
-        System.out.println("hello world!");
+        ShapeManager shapeManager = new ShapeManager();
+        Rectangle rect = new Rectangle(new Point(10, 10), 100, 200);
+        Triangle tri = new Triangle(new Point(0, 10), new Point(50, 50), new Point(150, 0));
+        Circle cir = new Circle(new Point(100, 100), 100);
 
+        shapeManager.addShape(rect);
+        shapeManager.addShape(tri);
+        shapeManager.addShape(cir);
+        shapeManager.drawShapes();
+        shapeManager.delShape(rect);
+        shapeManager.drawShapes();
     }
 }
diff --git a/src/main/java/cn/zust/edu/cn/Circle.java b/src/main/java/cn/zust/edu/cn/Circle.java
new file mode 100644
index 0000000000000000000000000000000000000000..1f185740b92aaa6c6611bcaac439dbdf84ac9146
--- /dev/null
+++ b/src/main/java/cn/zust/edu/cn/Circle.java
@@ -0,0 +1,26 @@
+package cn.zust.edu.cn;
+
+public class Circle implements IShape {
+    Point ptCenter;
+    int radius;
+
+    public Circle(Point center, int r) {
+        this.ptCenter = center;
+        this.radius = r;
+    }
+
+    @Override
+    public double perimeter() {
+        return 2 * Math.PI * radius;
+    }
+
+    @Override
+    public double area() {
+        return Math.PI * radius * radius;
+    }
+
+    @Override
+    public void draw() {
+        System.out.println("Drawing Circle at (" + ptCenter.x + ", " + ptCenter.y + ") with radius " + radius);
+    }
+}
\ No newline at end of file
diff --git a/src/main/java/cn/zust/edu/cn/IShape.java b/src/main/java/cn/zust/edu/cn/IShape.java
new file mode 100644
index 0000000000000000000000000000000000000000..017cdba67ea290ab631b8280cef0291c84a4d50f
--- /dev/null
+++ b/src/main/java/cn/zust/edu/cn/IShape.java
@@ -0,0 +1,7 @@
+package cn.zust.edu.cn;
+
+public interface IShape {
+    double perimeter();
+    double area();
+    void draw();
+}
diff --git a/src/main/java/cn/zust/edu/cn/Point.java b/src/main/java/cn/zust/edu/cn/Point.java
index 5661ad0dc525c7f45779a6b9a2d09b9be0a440b6..8d2a940bdaecfe1e8bdeaade52cecf1d2a3c09a0 100644
--- a/src/main/java/cn/zust/edu/cn/Point.java
+++ b/src/main/java/cn/zust/edu/cn/Point.java
@@ -5,5 +5,21 @@ package cn.zust.edu.cn;
  * @since 2023/3/7 10:50
  */
 public class Point {
+    int x;
+    int y;
 
-}
+    public Point() {
+        this.x = 0;
+        this.y = 0;
+    }
+
+    public Point(int x, int y) {
+        this.x = x;
+        this.y = y;
+    }
+
+    public Point(Point p) {
+        this.x = p.x;
+        this.y = p.y;
+    }
+}
\ No newline at end of file
diff --git a/src/main/java/cn/zust/edu/cn/Rectangle.java b/src/main/java/cn/zust/edu/cn/Rectangle.java
index f70897edc602cc78478ddfb7656749337bdd2cbe..4e578a3fddc8b045212fe221b46dc1e34d5d3b41 100644
--- a/src/main/java/cn/zust/edu/cn/Rectangle.java
+++ b/src/main/java/cn/zust/edu/cn/Rectangle.java
@@ -4,5 +4,38 @@ package cn.zust.edu.cn;
  * @author czg
  * @since 2023/3/7 10:50
  */
-public class Rectangle {
-}
+public class Rectangle implements IShape {
+    Point ptTopLeft;
+    Point ptTopRight;
+    int width;
+    int height;
+
+    public Rectangle() {
+        this.ptTopLeft = new Point();
+        this.ptTopRight = new Point();
+        this.width = 0;
+        this.height = 0;
+    }
+
+    public Rectangle(Point topleft, int height, int width) {
+        this.ptTopLeft = topleft;
+        this.ptTopRight = new Point(topleft.x + width, topleft.y);
+        this.width = width;
+        this.height = height;
+    }
+
+    @Override
+    public double perimeter() {
+        return 2 * (width + height);
+    }
+
+    @Override
+    public double area() {
+        return width * height;
+    }
+
+    @Override
+    public void draw() {
+        System.out.println("Drawing Rectangle at (" + ptTopLeft.x + ", " + ptTopLeft.y + ") with width " + width + " and height " + height);
+    }
+}
\ No newline at end of file
diff --git a/src/main/java/cn/zust/edu/cn/ShapeManager.java b/src/main/java/cn/zust/edu/cn/ShapeManager.java
new file mode 100644
index 0000000000000000000000000000000000000000..6e2ab98e0cd09157e1b0fe601a8d045069ffc2e5
--- /dev/null
+++ b/src/main/java/cn/zust/edu/cn/ShapeManager.java
@@ -0,0 +1,22 @@
+package cn.zust.edu.cn;
+
+import java.util.ArrayList;
+import java.util.List;
+
+public class ShapeManager {
+    private final List<IShape> shapes = new ArrayList<>();
+
+    public void addShape(IShape shape) {
+        shapes.add(shape);
+    }
+
+    public void delShape(IShape shape) {
+        shapes.remove(shape);
+    }
+
+    public void drawShapes() {
+        for (IShape shape : shapes) {
+            shape.draw();
+        }
+    }
+}
\ No newline at end of file
diff --git a/src/main/java/cn/zust/edu/cn/Triangle.java b/src/main/java/cn/zust/edu/cn/Triangle.java
new file mode 100644
index 0000000000000000000000000000000000000000..c7d6ec52a7a41634dcc6cd05cb0d0b0c1226dc01
--- /dev/null
+++ b/src/main/java/cn/zust/edu/cn/Triangle.java
@@ -0,0 +1,39 @@
+package cn.zust.edu.cn;
+
+public class Triangle implements IShape {
+    Point ptA;
+    Point ptB;
+    Point ptC;
+    double edgeA;
+    double edgeB;
+    double edgeC;
+
+    public Triangle(Point ptA, Point ptB, Point ptC) {
+        this.ptA = ptA;
+        this.ptB = ptB;
+        this.ptC = ptC;
+        this.edgeA = calculateDistance(ptA, ptB);
+        this.edgeB = calculateDistance(ptB, ptC);
+        this.edgeC = calculateDistance(ptC, ptA);
+    }
+
+    private double calculateDistance(Point p1, Point p2) {
+        return Math.sqrt(Math.pow(p2.x - p1.x, 2) + Math.pow(p2.y - p1.y, 2));
+    }
+
+    @Override
+    public double perimeter() {
+        return edgeA + edgeB + edgeC;
+    }
+
+    @Override
+    public double area() {
+        double s = perimeter() / 2;
+        return Math.sqrt(s * (s - edgeA) * (s - edgeB) * (s - edgeC));
+    }
+
+    @Override
+    public void draw() {
+        System.out.println("Drawing Triangle with vertices (" + ptA.x + ", " + ptA.y + "), (" + ptB.x + ", " + ptB.y + "), (" + ptC.x + ", " + ptC.y + ")");
+    }
+}
\ No newline at end of file
diff --git a/target/classes/cn/zust/edu/cn/App.class b/target/classes/cn/zust/edu/cn/App.class
new file mode 100644
index 0000000000000000000000000000000000000000..644d416730935062fc2a25cd69270c8f159abb54
Binary files /dev/null and b/target/classes/cn/zust/edu/cn/App.class differ
diff --git a/target/classes/cn/zust/edu/cn/Circle.class b/target/classes/cn/zust/edu/cn/Circle.class
new file mode 100644
index 0000000000000000000000000000000000000000..96c50f9510fe83719a32e59d62b2e12bcec7bf34
Binary files /dev/null and b/target/classes/cn/zust/edu/cn/Circle.class differ
diff --git a/target/classes/cn/zust/edu/cn/IShape.class b/target/classes/cn/zust/edu/cn/IShape.class
new file mode 100644
index 0000000000000000000000000000000000000000..2eacc522c098bb3ecf3b6e4098db6d3e398adcb2
Binary files /dev/null and b/target/classes/cn/zust/edu/cn/IShape.class differ
diff --git a/target/classes/cn/zust/edu/cn/Point.class b/target/classes/cn/zust/edu/cn/Point.class
new file mode 100644
index 0000000000000000000000000000000000000000..3922329b1f6c47e7700b0e9bf6c8855911baca3c
Binary files /dev/null and b/target/classes/cn/zust/edu/cn/Point.class differ
diff --git a/target/classes/cn/zust/edu/cn/Rectangle.class b/target/classes/cn/zust/edu/cn/Rectangle.class
new file mode 100644
index 0000000000000000000000000000000000000000..137515c0df0ea1035eded48e86f30bc8d887a509
Binary files /dev/null and b/target/classes/cn/zust/edu/cn/Rectangle.class differ
diff --git a/target/classes/cn/zust/edu/cn/ShapeManager.class b/target/classes/cn/zust/edu/cn/ShapeManager.class
new file mode 100644
index 0000000000000000000000000000000000000000..5271afff06afef4beaecb02b9c83f41ac997783c
Binary files /dev/null and b/target/classes/cn/zust/edu/cn/ShapeManager.class differ
diff --git a/target/classes/cn/zust/edu/cn/Triangle.class b/target/classes/cn/zust/edu/cn/Triangle.class
new file mode 100644
index 0000000000000000000000000000000000000000..ee89bbeac987e3af6ee23672e6dbb78f521458fb
Binary files /dev/null and b/target/classes/cn/zust/edu/cn/Triangle.class differ