Java: Template Method Pattern

 

/**
 * 版权所有 2022 涂聚文有限公司
 * 许可信息查看：
 * 描述：
 * 模板方法模式 Template Method Patterns
 * 历史版本： JDK 14.02
 * 2022-09-12 创建者 geovindu
 * 2022-09-12 添加 Lambda
 * 2022-09-12 修改：date
 * 接口类
 * 2022-09-12 修改者：Geovin Du
 * 生成API帮助文档的指令：
 *javadoc - -encoding Utf-8 -d apidoc Account.java
 *
 * */

package com.javapatterns.templatemethod;

/**
 *抽象类  账号
 * @author geovindu
 *
 * */
abstract public class Account {
    /**
     *
     *
     * */
    protected String accountNumber;
    /**
     *
     *
     * */
    public Account()
    {
        accountNumber = null;
    }
    /**
     *
     *
     * */
    public Account(String accountNumber)
    {
        this.accountNumber = accountNumber;
    }
    /**
     * 模板方法，计算利息数据数额
     * @return  返回利息数额
     * */
    final public double calculateInterest()
    {
        double interestRate = doCalculateInterestRate();
        String accountType = doCalculateAccountType();
        double amount = calculateAmount(accountType, accountNumber);

        return amount * interestRate;
    }
    /**
     *基本方法留给子类实现
     *账户类型
     * @return
     * */
    abstract protected String doCalculateAccountType() ;
    /**
     *基本方法留给子类实现
     * @return
     * */
    abstract protected double doCalculateInterestRate() ;
    /**
     *基本方法已经实现
     * @param accountType 输入类型
     * @param accountNumber  数字类型
     * @return
     * */
    final public double calculateAmount(String accountType, String accountNumber)
    {
        this.accountNumber=accountNumber;
        double rs=3.00D;
        if(accountType=="Certificate of Deposite" && accountNumber=="1")
        {
            rs=8888.00D;

        }
        if(accountType=="Certificate of Deposite" && accountNumber=="2")
        {
            rs=100000.00D;
        }

        if(accountType=="Money Market" && accountNumber=="1")
        {
            rs=8888.00D;

        }
        if(accountType=="Money Market" && accountNumber=="2")
        {
            rs=100000.00D;
        }
        return rs;
    }

}

　　

/**
 * 版权所有 2022 涂聚文有限公司
 * 许可信息查看：
 * 描述：
 * 模板方法模式 Template Method Patterns
 * 历史版本： JDK 14.02
 * 2022-09-12 创建者 geovindu
 * 2022-09-12 添加 Lambda
 * 2022-09-12 修改：date
 * 接口类
 * 2022-09-12 修改者：Geovin Du
 * 生成API帮助文档的指令：
 *javadoc - -encoding Utf-8 -d apidoc MoneyMarketAccount.java
 *
 * */



package com.javapatterns.templatemethod;
/**
 *货币市场账号
 * @author geovindu
 *
 * */
public class MoneyMarketAccount  extends Account {
    /**
     *基本方法这里实现
     *
     * @return
     * */
    public String doCalculateAccountType()
    {
        return "Money Market";
    }
    /**
     *基本方法这里实现
     *利率
     * @return
     * */
    public double doCalculateInterestRate()
    {
        return 0.045D;
    }



}

　　

/**
 * 版权所有 2022 涂聚文有限公司
 * 许可信息查看：
 * 描述：
 * 模板方法模式 Template Method Patterns
 * 历史版本： JDK 14.02
 * 2022-09-12 创建者 geovindu
 * 2022-09-12 添加 Lambda
 * 2022-09-12 修改：date
 * 接口类
 * 2022-09-12 修改者：Geovin Du
 * 生成API帮助文档的指令：
 *javadoc - -encoding Utf-8 -d apidoc CDAccount.java
 *
 * */


package com.javapatterns.templatemethod;
/**
 *具体子类 定期存款账号
 * @author geovindu
 * */
public class CDAccount extends Account {


    /**
     *基本方法这里实现
     * @return
     * */
    public String doCalculateAccountType()
    {
        return "Certificate of Deposite";
    }
    /**
     *基本方法这里实现
     *利率
     * @return
     * */
    public double doCalculateInterestRate()
    {
        return 0.065D;
    }
}

　　调用测试：

 //模板方法模式
            Account acct = null;
            acct = new MoneyMarketAccount();
            acct.calculateAmount("Money Market","1");
            System.out.println("Amount: 8888.00DInterest earned from Money Market account = " + acct.calculateInterest());
            acct = new CDAccount();
            acct.calculateAmount("Certificate of Deposite","1");
            System.out.println("Amount: 8888.00D Interest earned from CD account = " + acct.calculateInterest());

            acct = new MoneyMarketAccount();
            acct.calculateAmount("Money Market","2");
            System.out.println("Amount: 100000.00D  Interest earned from Money Market account = " + acct.calculateInterest());
            acct = new CDAccount();
            acct.calculateAmount("Certificate of Deposite","2");
            System.out.println("Amount: 100000.00D  Interest earned from CD account = " + acct.calculateInterest());

　　

输出：

Amount: 8888.00DInterest earned from Money Market account = 399.96
Amount: 8888.00D Interest earned from CD account = 577.72
Amount: 100000.00D  Interest earned from Money Market account = 4500.0
Amount: 100000.00D  Interest earned from CD account = 6500.0