public abstract class Component
 {
     public abstract void add(Component c);
     public abstract void remove(Component c);
     public abstract Component getChild(int i);
     public abstract void operation(); 
 } 

 public class Leaf extends Component
 {
     public void add(Component c)
     { //異常處理或錯誤提示 }    
     public void remove(Component c)
     { //異常處理或錯誤提示 }
     public Component getChild(int i)
     { //異常處理或錯誤提示 }
     public void operation()
     {
         //實現(xiàn)代碼
     } 
 } 

 //抽象構(gòu)建
 public abstract class MyElement
 {
     public abstract void eat();
 }
 //容器構(gòu)建
 import java.util.*;
 public class Plate extends MyElement
 {
     private ArrayList list=new ArrayList();
     public void add(MyElement element)
     {
      list.add(element);    
     }
     public void delete(MyElement element)
     {
         list.remove(element);
     }
     public void eat()
     {
         for(Object object:list)
         {
             ((MyElement)object).eat();    //遞歸
         }
     }
 }
 //葉子構(gòu)建
 public class Apple extends MyElement
 {
     public void eat()
     {
         System.out.println("吃蘋果！");
     }
 }
 //葉子構(gòu)建
 public class Banana extends MyElement
 {
     public void eat()
     {
         System.out.println("吃香蕉！");
     }
 }
 //葉子構(gòu)建
 public class Pear extends MyElement
 {
     public void eat()
     {
        System.out.println("吃梨子！");
     }
 }
 //客戶端
 public class Client
 {
     public static void main(String a[])
     {
         MyElement obj1,obj2,obj3,obj4,obj5;
         Plate plate1,plate2,plate3;
         obj1=new Apple();
         obj2=new Pear();
         plate1=new Plate();
         plate1.add(obj1);
         plate1.add(obj2);
         obj3=new Banana();
         obj4=new Banana();
         plate2=new Plate();
         plate2.add(obj3);
         plate2.add(obj4);
         obj5=new Apple();
         plate3=new Plate();
         plate3.add(plate1);
        plate3.add(plate2);
         plate3.add(obj5);
         plate3.eat();
     }
 }

public abstract class Component {
    public String getName() {
        throw new UnsupportedOperationException("不支持獲取名稱操作");
    }
    public void add(Component component) {
        throw new UnsupportedOperationException("不支持添加操作");
    }
    public void remove(Component component) {
        throw new UnsupportedOperationException("不支持刪除操作");
    }
    public void print() {
        throw new UnsupportedOperationException("不支持打印操作");
    }
    public String getContent() {
        throw new UnsupportedOperationException("不支持獲取內(nèi)容操作");
    }
}

public class Folder extends Component {
    private String name;
    private List<Component> componentList = new ArrayList<Component>();
      public Integer level;
    public Folder(String name) {
        this.name = name;
    }
    @Override
    public String getName() {
        return this.name;
    }
    @Override
    public void add(Component component) {
        this.componentList.add(component);
    }
    @Override
    public void remove(Component component) {
        this.componentList.remove(component);
    }
     @Override
    public void print() {
        System.out.println(this.getName());
        if (this.level == null) {
            this.level = 1;
        }
        String prefix = "";
        for (int i = 0; i < this.level; i++) {
            prefix += "\t- ";
        }
        for (Component component : this.componentList) {
            if (component instanceof Folder){
                ((Folder)component).level = this.level + 1;
            }
            System.out.print(prefix);
            component.print();
        }
        this.level = null;
    }
}

public class File extends Component {
    private String name;
    private String content;
    public File(String name, String content) {
        this.name = name;
        this.content = content;
    }
    @Override
    public String getName() {
        return this.name;
    }
    @Override
    public void print() {
        System.out.println(this.getName());
    }
    @Override
    public String getContent() {
        return this.content;
    }
}

public class Test {
    public static void main(String[] args) {
        Folder DSFolder = new Folder("設(shè)計模式資料");
        File note1 = new File("組合模式筆記.md", "組合模式組合多個對象形成樹形結(jié)構(gòu)以表示具有 \"整體—部分\" 關(guān)系的層次結(jié)構(gòu)");
        File note2 = new File("工廠方法模式.md", "工廠方法模式定義一個用于創(chuàng)建對象的接口，讓子類決定將哪一個類實例化。");
        DSFolder.add(note1);
        DSFolder.add(note2);
        Folder codeFolder = new Folder("樣例代碼");
        File readme = new File("README.md", "# 設(shè)計模式示例代碼項目");
        Folder srcFolder = new Folder("src");
        File code1 = new File("組合模式示例.java", "這是組合模式的示例代碼");
        srcFolder.add(code1);
        codeFolder.add(readme);
        codeFolder.add(srcFolder);
        DSFolder.add(codeFolder);
        DSFolder.print();
    }
}

 1 <?xml version="1.0"?>
 2   <books>
 3     <book>
 4         <author>Carson</author>
 5         <price format="dollar">31.95</price>
 6         <pubdate>05/01/2001</pubdate>
 7     </book>
 8     <pubinfo>
 9         <publisher>MSPress</publisher>
10         <state>WA</state>
11     </pubinfo>
12   </books> 

public class Test {
    public static void main(String[] args) {
        Map<String, Integer> map1 = new HashMap<String, Integer>();
        map1.put("aa", 1);
        map1.put("bb", 2);
        map1.put("cc", 3);
        System.out.println("map1: " + map1);
        Map<String, Integer> map2 = new LinkedMap();
        map2.put("cc", 4);
        map2.put("dd", 5);
        System.out.println("map2: " + map2);
        map1.putAll(map2);
        System.out.println("map1.putAll(map2): " + map1);
    }
}

public void putAll(Map<? extends K, ? extends V> m) {
        putMapEntries(m, true);
    }

<select id="findActiveBlogLike"  resultType="Blog">
  SELECT * FROM BLOG WHERE state = ‘ACTIVE' 
  <if test="title != null">
    AND title like #{title}
  </if>
  <if test="author != null and author.name != null">
    AND author_name like #{author.name}
  </if>
</select>

public interface SqlNode {
  boolean apply(DynamicContext context);
}

public class MixedSqlNode implements SqlNode {
  private List<SqlNode> contents;
  public MixedSqlNode(List<SqlNode> contents) {
    this.contents = contents;
  }
  @Override
  public boolean apply(DynamicContext context) {
    for (SqlNode sqlNode : contents) {
      sqlNode.apply(context);
    }
    return true;
  }
}