不使用Sqoop流程，利用CacheManager直接完成SparkSQL數據流直接回寫Oracle

以前都是使用Sqoop來完成數據從生成的hdfs數據存儲上來抽取至oracle的數據庫：sqoop抽取語句：
sqoop export --connect "jdbc:oracle:thin:@ip:port:sid" --username 用戶名 --password 密碼 --table sid.表名 --export-dir hdfs://nameservice1/user/XXX(hdfs地址) --fields-terminated-by "\001" --null-non-string '' --null-string '' -m 10;

 由于項目需求我們現在要完成在代碼中省城所需字段之后，直接回寫到oracle中，因為數據量每天都很大，用實例或者List存有很大的局限性，可能會出現內存異常等不可預料的東西，所以我通過緩存器機制來存儲數據，然后進行生成結果的臨時表直接回寫（后面做的hbase接口封裝批量提交也比較類似）
 廢話不多說直接上代碼：
 1、建立緩存實體
 package usi.java.oracle;

/**

• @author HK

• @date 2011-2-15 下午06:45:57
  */
  public class Cache {
  private String key;
  private Object value;
  private long timeOut;
  private boolean expired;
  public Cache() {
  super();
  }

  public Cache(String key, String value, long timeOut, boolean expired) {
  this.key = key;
  this.value = value;
  this.timeOut = timeOut;
  this.expired = expired;
  }

  public String getKey() {
  return key;
  }

  public long getTimeOut() {
  return timeOut;
  }

  public Object getValue() {
  return value;
  }

  public void setKey(String string) {
  key = string;
  }

  public void setTimeOut(long l) {
  timeOut = l;
  }

  public void setValue(Object object) {
  value = object;
  }

  public boolean isExpired() {
  return expired;
  }

  public void setExpired(boolean b) {
  expired = b;
  }
  }

2、建立緩存控制器
package usi.java.oracle;

import java.util.Date;
import java.util.HashMap;

/**

• @author HK

• @date 2011-2-15 下午09:40:00
  */
  public class CacheManager {

  private static HashMap cacheMap = new HashMap();

  /**

  • This class is singleton so private constructor is used.
    */
    private CacheManager() {
    super();
    }

    /**

  • returns cache item from hashmap
  • @param key

  • @return Cache
    */
    private synchronized static Cache getCache(String key) {
    return (Cache)cacheMap.get(key);
    }

    /**

  • Looks at the hashmap if a cache item exists or not
  • @param key

  • @return Cache
    */
    private synchronized static boolean hasCache(String key) {
    return cacheMap.containsKey(key);
    }

    /**

  • Invalidates all cache
    */
    public synchronized static void invalidateAll() {
    cacheMap.clear();
    }

    /**

  • Invalidates a single cache item

  • @param key
    */
    public synchronized static void invalidate(String key) {
    cacheMap.remove(key);
    }

    /**

  • Adds new item to cache hashmap
  • @param key

  • @return Cache
    */
    private synchronized static void putCache(String key, Cache object) {
    cacheMap.put(key, object);
    }

    /**

  • Reads a cache item's content
  • @param key

  • @return
    */
    public static Cache getContent(String key) {
    if (hasCache(key)) {
    Cache cache = getCache(key);
    if (cacheExpired(cache)) {
    cache.setExpired(true);
    }
    return cache;
    } else {
    return null;
    }
    }

    /**

  • @param key
  • @param content

  • @param ttl
    */
    public static void putContent(String key, Object content, long ttl) {
    Cache cache = new Cache();
    cache.setKey(key);
    cache.setValue(content);
    cache.setTimeOut(ttl + new Date().getTime());
    cache.setExpired(false);
    putCache(key, cache);
    }

    /* @modelguid {172828D6-3AB2-46C4-96E2-E72B34264031} /
    private static boolean cacheExpired(Cache cache) {
    if (cache == null) {
    return false;
    }
    long milisNow = new Date().getTime();
    long milisExpire = cache.getTimeOut();
    if (milisExpire < 0) { // Cache never expires
    return false;
    } else if (milisNow >= milisExpire) {
    return true;
    } else {
    return false;
    }
    }

}

3、建立需要導出數據對象
package usi.java.oracle;

public class TaskAll {
private String mme_eid;
private String mme_editor;
private String entitytype_eid;
private String project_eid;
private String resource_eid;
public String getMme_eid() {
return mme_eid;
}
public void setMme_eid(String mme_eid) {
this.mme_eid = mme_eid;
}
public String getMme_editor() {
return mme_editor;
}
public void setMme_editor(String mme_editor) {
this.mme_editor = mme_editor;
}
public String getEntitytype_eid() {
return entitytype_eid;
}
public void setEntitytype_eid(String entitytype_eid) {
this.entitytype_eid = entitytype_eid;
}
public String getProject_eid() {
return project_eid;
}
public void setProject_eid(String project_eid) {
this.project_eid = project_eid;
}
public String getResource_eid() {
return resource_eid;
}
public void setResource_eid(String resource_eid) {
this.resource_eid = resource_eid;
}

}
5、執行邏輯主體，回寫數據，批量提交

package usi.java.oracle;

import java.sql.Connection;
import java.sql.DriverManager;
import java.sql.PreparedStatement;
//import java.sql.ResultSet;
import java.util.List;

import org.apache.spark.SparkConf;
import org.apache.spark.SparkContext;
import org.apache.spark.sql.DataFrame;
import org.apache.spark.sql.Row;
import org.apache.spark.sql.hive.HiveContext;

public class redict_to_171ora {
public static void main(String[] args) {
SparkConf sc = new SparkConf().setAppName("redict_to_171ora");
SparkContext jsc = new SparkContext(sc);
HiveContext hc = new HiveContext(jsc);
String hivesql1="select t.mme_eid,t.mme_editor,t.entitytype_eid,t.project_eid,t.resource_eid from usi_odso.c_taskall t limit 150000";

    DataFrame redict_to_171ora= hc.sql(hivesql1);
    //redict_to_171ora.registerTempTable("hivesql1");       
    List<Row> collect=redict_to_171ora.javaRDD().collect();

    int o=0;
    for (Row lists: collect){
        TaskAll task=new TaskAll();
        task.setMme_eid(lists.getString(0));
        task.setMme_editor(lists.getString(1));
        task.setEntitytype_eid(lists.getString(2));
        task.setProject_eid(lists.getString(3));
        task.setResource_eid(lists.getString(4));
        CacheManager.putContent(o+"", task, 30000000);
        o++;
    /* System.out.println(lists.size());
     System.out.println(lists.getString(0));
     System.out.println(lists.getString(1));
     System.out.println(lists.getString(2));
     System.out.println(lists.getString(3));
     System.out.println(lists.getString(4));*/
      }
    System.out.println(o);

        Connection con = null;// 創建一個數據庫連接
        PreparedStatement pre = null;// 創建預編譯語句對象，一般都是用這個而不用Statement
        //ResultSet result = null;// 創建一個結果集對象
        try
        {
            Class.forName("oracle.jdbc.driver.OracleDriver");// 加載Oracle驅動程序
            System.out.println("開始嘗試連接數據庫！");
            String url = "jdbc:oracle:" + "thin:@ip:1521:sid";// 127.0.0.1是本機地址，XE是精簡版Oracle的默認數據庫名
            String user = "user";// 用戶名,系統默認的賬戶名
            String password = "password";// 你安裝時選設置的密碼
            con = DriverManager.getConnection(url, user, password);// 獲取連接
            System.out.println("連接成功！");
            String sql = "insert into c_taskall_test(mme_eid,mme_editor,entitytype_eid,project_eid,resource_eid) values(?,?,?,?,?)";// 預編譯語句，“？”代表參數
            pre = con.prepareStatement(sql);// 實例化預編譯語句
            for(int i=0;i<o;i++){
           // for (Row lists: collect){             
           // String sql = "insert into c_taskall_test(mme_eid,mme_editor,entitytype_eid,project_eid,resource_eid) values('"+task.getMme_eid()+"','"+task.getMme_editor()+"','"+task.getEntitytype_eid()+"','"+task.getProject_eid()+"','"+task.getResource_eid()+"')";// 預編譯語句，“？”代表參數                                         
           // pre.setString(1, "三星");// 設置參數，前面的1表示參數的索引，而不是表中列名的索引
            TaskAll task=(TaskAll) CacheManager.getContent(""+i).getValue();
            pre.setString(1, task.getMme_eid());
            pre.setString(2, task.getMme_editor());
            pre.setString(3, task.getEntitytype_eid());
            pre.setString(4, task.getProject_eid());
            pre.setString(5, task.getResource_eid());
            pre.addBatch(); 
            if(i%20000==0){//可以設置不同的大小；如50，100，500，1000等等      
            pre.executeBatch();      
            con.commit();      
            pre.clearBatch();      
           // System.out.println("i的值"+i);
            }
           // result = pre.executeQuery();// 執行查詢，注意括號中不需要再加參數             
            }
            pre.executeBatch();      
            con.commit();      
            pre.clearBatch();      
           // System.out.println("i的值"+i);
          /*  if (result != null)
                result.close();*/
            if (pre != null)
                pre.close();
           /* while (result.next())
                // 當結果集不為空時
                System.out.println("usernum:" + result.getString("usernum") + "flow:"
                        + result.getString("flow"));*/
           }
        catch (Exception e)
        {
            e.printStackTrace();
        }
        finally
        {
            try
            {
                // 逐一將上面的幾個對象關閉，因為不關閉的話會影響性能、并且占用資源
                // 注意關閉的順序，最后使用的最先關閉
              /*  if (result != null)
                    result.close();*/
                if (pre != null)
                    pre.close();
                if (con != null)
                    con.close();
                //System.out.println("數據庫連接已關閉！");
            }
            catch (Exception e)
            {
                e.printStackTrace();
            }
        }

    }

}