使用Java的IO流拼接SQL语句

分手后的思念是犯贱 2023-06-11 08:23 1阅读 0赞

**使用IO流拼接SQL语句**  
读取txt文件的内容；然后拼接成SQL语句后输出到txt文件。

import java.io.BufferedReader;
    import java.io.BufferedWriter;
    import java.io.File;
    import java.io.FileInputStream;
    import java.io.FileWriter;
    import java.io.IOException;
    import java.io.InputStreamReader;
    import java.util.ArrayList;
    import java.util.Collection;
    import java.util.Iterator;
    
    public class IOStreams { 
    
    	public static void main(String[] args) { 
    		// 读数据（相对路径）
    		String readFileName = ".\\source\\test_1029.txt"; 
    		Collection coll = readFiles(readFileName);
    		System.out.println("上传的数据总条数："+ coll.size());
    		
    		// 写数据（相对路径）
    		String writeFileName = ".\\source\\test_point_1029.txt";
    		int num = writeFiles(writeFileName, coll);
    		System.out.println("写入的数据总条数：" + num);
    	}
    	
    	/** * 读取txt文件入集合 * @param pathName * @return * @throws IOException */
    	public static Collection readFiles(String pathName) { 
    		Collection coll = new ArrayList<>();
    		File file = null;
    		InputStreamReader reader = null;
    		String line = null;
    		try { 
    			file = new File(pathName);
    			// 建立一个输入流对象reader
    			reader = new InputStreamReader(new FileInputStream(file));
    			// 建立一个对象，它把文件内容转成计算机能读懂的语言
                BufferedReader br = new BufferedReader(reader);
                while (br.ready()) {  
                	// (line = br.readLine())!=null,会出现漏读首行，文末行为null
                	// 可以用br.ready()解决
                	// 一次读入一行数据 
                    line = br.readLine();
                    //System.out.println(line);
                    // 添加
                    coll.add(line);
                } 
    		} catch (Exception e) { 
    			e.printStackTrace();
    		} finally { 
    			if(null != reader)
    				try { 
    					reader.close();
    				} catch (IOException e) { 
    					// TODO Auto-generated catch block
    					e.printStackTrace();
    				}
    		}
    		return coll;
    	}
    	
    	/** * 把拼接后的sql语句写回txt文件 * @param pathName 文件的路径 * @param line 数据 */
    	public static int writeFiles(String pathName,Collection coll){ 
    		File writename = new File(pathName);
    		BufferedWriter out = null;
    		// 计数,统计写入的条数
    		int count = 0;
    		try { 
    			// 每次都创建新文件 
    			writename.createNewFile(); 
    			out = new BufferedWriter(new FileWriter(writename));  
    			for(Iterator iter = coll.iterator(); iter.hasNext();){ 
    				// \r\n即为换行
    				out.write("INSERT INTO test (phone,souce) VALUES ('"+iter.next()+"','test');\r\n");   
    		        out.flush(); // 把缓存区内容压入文件 
    		        count ++;
    			}
    		} catch (Exception e) { 
    			e.printStackTrace();
    		} finally { 
    			if(null != out)
    				try { 
    					out.close();
    				} catch (IOException e) { 
    					// TODO Auto-generated catch block
    					e.printStackTrace();
    				} 
    		}
    		return count;
    	}
    }