SAP接口编程 之 JCo3.0系列(01):JCoDestination

SAP接口编程 之 JCo3.0系列(01):JCoDestination

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JCo3.0是Java语言与ABAP语言双向通讯的中间件。与之前1.0/2.0相比,是重新设计的产品。API和架构设计与NCo3.0比较类似,前面也说过,NCo3.0的设计参考了JCo3.0。从本篇开始,系统介绍JCo3.0编程的技术要点。

JCo3.0安装

https://service.sap.com/connectors 可以下载JCo3.0,注意下载的时候根据操作系统JVM版本(32位还是64)选择不同的版本。安装就是解压,将文件解压到目标文件夹。以Windows系统为例,主要的文件包括:

sapjco3.dll
sapjco3.jar

SAP强烈推荐将这两个文件放在同一文件夹下。测试安装是否成功,可以在命令窗口下,进入安装文件夹,运行下面的命令:

java -jar sapjco3.jar

如果安装成功,应该显示如下界面:


jco3安装成功的显示界面

JCoDestination

JCoDestination代表后台SAP系统,程序员不用关心与SAP的连接,jco3.0运行时环境负责管理连接和释放连接。我们先以一个简单的例子看看jco3.0 JCoDestination类的一些要点。

我使用的编程环境是Eclipse,环境准备如下:

  • 新建一个Java项目,项目名为JCo3Demo。
  • 将sapjco3.jar加入到项目的build path中。注意前面所说的sapjco3.jar和sapjco3.dll要放在同一个文件夹下。
  • 在Eclipse Java项目文件夹下,新建一个文本文件,文件名命名为ECC.jocdestination, 文件的内容如下(SAP系统的连接参数的设置):

    #SAP Logon parameters!
    #Tue Dec 08 16:41:30 CST 2015
    jco.client.lang=EN
    jco.client.client=001
    jco.client.passwd=xxxxxx
    jco.client.user=STONE
    jco.client.sysnr=00
    jco.client.ashost=192.168.65.100

对照SAP GUI,不难理解:


SAP GUI

环境准备好了,先来一段最简单的代码:

package jco3.demo1;

import java.util.Properties;
import org.junit.Test;
import com.sap.conn.jco.JCoDestination;
import com.sap.conn.jco.JCoDestinationManager;
import com.sap.conn.jco.JCoException;

public class JCoDestinationDemo
{
    public JCoDestination getDestination() throws JCoException
    {
        /**
         * Get instance of JCoDestination from file: ECC.jcodestination
         * which should be located in the installation folder of project
         */

        JCoDestination dest = JCoDestinationManager.getDestination("ECC");
        return dest;
    }

    @Test
    public void pingDestination() throws JCoException
    {     
        JCoDestination dest = this.getDestination();
        dest.ping();
    }    
}

代码说明:

  • getDestination()方法中,JCoDestinationManager.getDestination("ECC")从ECC.jcodestination文件中获取连接参数,创建JCoDestination对象的实例。
    这里有一个重要的约定,JCoDestinationManager.getDestination("ECC")方法,会从Eclipse Java项目的根目录,查找ECC.jcodestination文件(文件路径和扩展名不能改变)是否存在,如果存在,从文件的内容中获取连接参数。这是DestinationDataProvider接口的一个默认实现,在开发和测试的时候还是很方便的,但如果在真实项目中使用,安全性和灵活性就不够。后面会介绍解决方法。

  • pingDestination()方法调用JcoDestination对象的ping()方法测试SAP系统的连接。

  • @Test: 使用junit进行测试

配置文件的生成

刚才我们手工编辑了ECC.jcodestination文件,对于这个配置文件,因为很多连接参数来自于DestinationDataProvider接口,如果想通过代码来创建配置文件,可以使用如下代码:

package jco3.demo2;

import java.io.File;
import java.io.FileNotFoundException;
import java.io.FileOutputStream;
import java.io.IOException;
import java.util.Properties;
import org.junit.Test;
import com.sap.conn.jco.ext.DestinationDataProvider;

public class DestinationFile
{
    private Properties setProperties()
    {        
        // logon parameters and other properties
        Properties connProps = new Properties();
        connProps.setProperty(DestinationDataProvider.JCO_ASHOST, "192.168.65.100");
        connProps.setProperty(DestinationDataProvider.JCO_SYSNR, "00");
        connProps.setProperty(DestinationDataProvider.JCO_USER, "STONE");
        connProps.setProperty(DestinationDataProvider.JCO_PASSWD, "xxxxxx");
        connProps.setProperty(DestinationDataProvider.JCO_CLIENT, "001");
        connProps.setProperty(DestinationDataProvider.JCO_LANG, "EN");

        return connProps;
    }

    private void doCreateFile(String fName, String suffix, Properties props) throws IOException
    {
        /**
         * Write contents of properties into a text file
         * which was named [fName+suffix.jcodestination]
         */

        File cfg = new File(fName+"."+suffix);
        if (!cfg.exists()){ // file not exists
            // Create file output stream, not using append mode
            FileOutputStream fOutputStream = new FileOutputStream(cfg, false); 

            // store the properties in file output stream
            // and also add comments
            props.store(fOutputStream, "SAP logon parameters:"); 

            fOutputStream.close();
        }else{
            throw new RuntimeException("File alreay exists.");
        }
    }

    @Test
    public void createConfigFile() throws IOException
    {        
        Properties props = this.setProperties();
        String fileName = "SAP_AS"; // sap application server

        // jcodestination suffix is required by JCoDestinationManager
        this.doCreateFile(fileName, "jcodestination", props);
    }
}

代码说明:

  • setProperties()方法属性参照DestinationDataProvider类的常量设置Properties的实例。
  • doCreateFile()方法根据需求的文件名,扩展名在Eclipse项目的根文件夹下,创建一个文本文件,文件的内容就是Properties实例的内容。
  • createConfigFile()方法,调用上面的两个方法,创建配置文件。

更改配置文件名的路径和扩展名

我们看到,默认情况下,SAP对配置文件的路径和扩展名都不能改变,如果我们想把文件放在任意位置,扩展名也使用其他的扩展名,有没有办法?答案是有,方法是实现DestinationDataProvider接口,并改写(override)getDestinationProperties()方法,然后通过Environment.registerDestinationDataProvider()方法进行注册。

OK, 一起来看看代码,代码分为三个部分:

  • 第一部分: 创建FileDestinationDataProviderImp类,实现DestinationDataProvider接口
  • 第二部分: 创建FileDestinationDataProvider类,注册FileDestinationDataProviderImp的实例,并提供getDestination()方法供调用
  • 第三部分:调用FileDestinationDataProvider类的getDestination()方法

第一部分:DestinationDataProvider接口的实现:

package jco3.demo2;

import java.io.File;
import java.io.FileInputStream;
import java.io.IOException;
import java.util.Properties;
import com.sap.conn.jco.ext.DestinationDataEventListener;
import com.sap.conn.jco.ext.DestinationDataProvider;

public class FileDestinationDataProviderImp implements DestinationDataProvider
{    
    private File dir;
    private String destName; // destination name
    private String suffix;

    public void setDestinationFile(File dir, String destName, String suffix)
    {
        this.dir = dir;
        this.destName = destName;
        this.suffix = suffix;
    }

    private Properties loadProperties(File dir, String destName, String suffix) throws IOException
    {
        Properties props = null;

        // create a file with name: fullName in destDirectory
        File destFile = new File(dir, destName+"."+suffix);

        if (destFile.exists()){
            FileInputStream fInputStream = new FileInputStream(destFile);
            props = new Properties();
            props.load(fInputStream);
            fInputStream.close();            
        }else{
            throw new RuntimeException("Destination file does not exist.");
        }    

        return props;
    }

    @Override
    public Properties getDestinationProperties(String destName)
    {        
        Properties props = null;

        try {
            props = this.loadProperties(this.dir, this.destName, this.suffix);
        } catch (IOException e) {            
            e.printStackTrace();
        }        

        return props;
    }

    @Override
    public void setDestinationDataEventListener(DestinationDataEventListener listener)
    {
        throw new UnsupportedOperationException();
    }

    @Override
    public boolean supportsEvents()
    {        
        return false;
    }
}

第二部分: 创建FileDestinationDataProvider类,注册FileDestinationDataProviderImp的实例,并且提供getDestination()方法。

package jco3.demo2;

import java.io.File;
import com.sap.conn.jco.JCoDestination;
import com.sap.conn.jco.JCoDestinationManager;
import com.sap.conn.jco.JCoException;
import com.sap.conn.jco.ext.Environment;

public class FileDestinationDataProvider
{    
    public static JCoDestination getDestination() throws JCoException    
    {    
        File directory = new File("."); // current directory;
        String fileName = "SAP_AS";
        String suffix = "txt";

        FileDestinationDataProviderImp destDataProvider = new FileDestinationDataProviderImp();
        destDataProvider.setDestinationFile(directory, fileName, suffix);        
        Environment.registerDestinationDataProvider(destDataProvider);

        JCoDestination dest = JCoDestinationManager.getDestination(fileName);

        return dest;        
    }
}

我们看到,getDestination方法中,文件的路径,文件的扩展名,都是我们自己定义的。文件名作为JCoDestinationManager.getDestination方法的destination name。从这里也可可以看到,JCoDestinationManager.getDestination方法从哪里查找连接参数,是依赖于Environment注册的DestinationDataProvider实现

第三部分:测试代码FileDestinationDataProvidergetDestination方法:

package jco3.demo2;

import org.junit.Test;
import com.sap.conn.jco.JCoDestination;
import com.sap.conn.jco.JCoException;

public class TestFileDestinationProvider
{
    @Test
    public void pingSAPDestination() throws JCoException
    {
        JCoDestination dest = FileDestinationDataProvider.getDestination();
        dest.ping();
    }
}

DestinationDataProvider另一种实现

记得nco3.0可以将登陆参数写在代码中吗,如果我们也想将连接参数直接写在代码中,怎么做呢?刚才说过了,关键就是实现DestinationDataProvider接口,并改写getDestinationProperties()方法。不多说,上代码。

第一部分:DestinationDataProvider接口实现

package jco3.demo3;

import java.util.HashMap;
import java.util.Map;
import java.util.Properties;
import com.sap.conn.jco.ext.DestinationDataEventListener;
import com.sap.conn.jco.ext.DestinationDataProvider;

public class DestinationDataProviderImp implements DestinationDataProvider
{
    /**
     * DestinationDataProvider is an interface
     * We define DestinationDataProviderImp class to implements this interface
     * so that we can define the logon parameters more flexibly
     * not just in xxx.jcodestionation file.
     * 
     * The key point is that we override getDestinationProperties() method
     * Afterwards, instance of DestinationDataProvider should be registered
     * using Environment.registerDestinationDataProvider() method to take effect
     */

    @SuppressWarnings("rawtypes")
    private Map provider = new HashMap();

    @SuppressWarnings("unchecked")
    public void addDestinationProperties(String destName, Properties props)
    {
        provider.put(destName, props);
    }

    @Override
    public Properties getDestinationProperties(String destName)
    {        
        if (destName == null){
            throw new NullPointerException("Destinantion name is empty.");
        }

        if (provider.size() == 0){
            throw new IllegalStateException("Data provider is empty.");
        }

        return (Properties) provider.get(destName);
    }

    @Override
    public void setDestinationDataEventListener(DestinationDataEventListener listener)
    {
        throw new UnsupportedOperationException();
    }

    @Override
    public boolean supportsEvents()
    {        
        return false;
    }
}

第二部分:创建DestinationProivder类,提供getDestination()方法,注册DestinationDataProviderImp类的实例:

package jco3.demo3;

import java.util.Properties;
import com.sap.conn.jco.JCoDestination;
import com.sap.conn.jco.JCoDestinationManager;
import com.sap.conn.jco.JCoException;
import com.sap.conn.jco.ext.DestinationDataProvider;
import com.sap.conn.jco.ext.Environment;

public class DestinationProvider
{    
    private static Properties setProperties()
    {    
        // logon parameters and other properties
        Properties connProps = new Properties();        
        connProps.setProperty(DestinationDataProvider.JCO_ASHOST, "192.168.65.100");
        connProps.setProperty(DestinationDataProvider.JCO_SYSNR, "00");
        connProps.setProperty(DestinationDataProvider.JCO_USER, "STONE");
        connProps.setProperty(DestinationDataProvider.JCO_PASSWD, "xxxxxx");
        connProps.setProperty(DestinationDataProvider.JCO_CLIENT, "001");
        connProps.setProperty(DestinationDataProvider.JCO_LANG, "EN");

        return connProps;        
    }

    public static JCoDestination getDestination() throws JCoException
    {
        String destName = "SAP_AS";

        Properties props = setProperties();        
        DestinationDataProviderImp destDataProvider = new DestinationDataProviderImp();
        destDataProvider.addDestinationProperties(destName, props);
        Environment.registerDestinationDataProvider(destDataProvider);

        JCoDestination dest = JCoDestinationManager.getDestination(destName);
        return dest;        
    }
}

第三部分:测试DestinationProvidergetDestination()方法:

package jco3.demo3;

import org.junit.Test;
import com.sap.conn.jco.JCoDestination;
import com.sap.conn.jco.JCoException;

public class TestDestionProvider
{
    @Test
    public void pingSAPDestination() throws JCoException
    {
        JCoDestination dest = DestinationProvider.getDestination();
        dest.ping();
    }
}
posted @ 2016-07-14 13:57  zfswff  阅读(8858)  评论(0编辑  收藏  举报