需求：需要组装复杂结构的实例

代码清单：

Builder 接口：

1 public abstract class Builder {2 3     public abstract  void makeTitle(String title);4     public abstract  void makeString(String str);5     public abstract  void makeItems(String[] itens);6     public abstract  void close();7 }

实现1：

public class HtmlBuilder extends Builder{    private String filename;    private PrintWriter writer;    @Override    public void makeTitle(String title) {        filename= title+".html";        try{            writer = new PrintWriter(new FileWriter(filename));        }catch (IOException E){            E.printStackTrace();        }        writer.println("");        writer.println("
"+title+"
");    }    @Override    public void makeString(String str) {        writer.println("
"+str+"
");    }    @Override    public void makeItems(String[] itens) {        writer.println("ul");        for(int i=0;i
     
      ");        }        writer.println("");    }    @Override    public void close() {        writer.println("");        writer.close();    }    public String  getResult(){        return filename;    }}
     

实现2：

public class TextBuilder extends Builder{    private StringBuffer buffer = new StringBuffer();    @Override    public void makeTitle(String title) {        buffer.append("===============================\n");        buffer.append("["+title+"]");        buffer.append("\n");    }    @Override    public void makeString(String str) {        buffer.append("|"+str+"|");        buffer.append("\n");    }    @Override    public void makeItems(String[] itens) {        for(int i=0;i

指挥者：

public class Director {    private Builder builder;    public Director(Builder builder){        this.builder = builder;    }    public void construct(){        builder.makeTitle("Greeting");        builder.makeString("上午-下午");        builder.makeItems(new String[]{                "good morning",                "good night"        });        builder.makeString("晚上");        builder.makeItems(new String[]{                "good night",                "bye"        });        builder.close();    }}

测试：

public class Main {    public static void main(String[] args){            TextBuilder textBuilder = new TextBuilder();            Director director = new Director(textBuilder);            director.construct();            String result = textBuilder.getResult();            System.out.println(result);            HtmlBuilder htmlBuilder = new HtmlBuilder();            Director director2 = new Director(htmlBuilder);            director2.construct();            String fileName = htmlBuilder.getResult();            System.out.println(fileName+"complete");            System.exit(0);    }}