在eclipse中postgreSQL的访问问题
- Java code
package jp.bcat;import java.sql.*;import java.util.Vector;public class DatabaseBookCatalog extends BookCatalog { Connection connection; static final String DATABASE_URL = "jdbc:postgresql://127.0.0.1/bcat"; static final String DATABASE_USER = "bcat"; static final String DATABASE_PASSWORD = "secret"; public DatabaseBookCatalog() { connect(); } protected boolean connect() { try { if (connection != null) { if (connection.getWarnings() == null) return true; disconnect(); } DriverManager.registerDriver(new org.postgresql.Driver()); connection = DriverManager.getConnection(DATABASE_URL, DATABASE_USER, DATABASE_PASSWORD); if (connection.getWarnings() == null) return true; disconnect(); } catch (Exception ex) { ex.printStackTrace(); } return false; } protected void disconnect() { if (connection != null) { try { connection.close(); } catch (Exception ex) { ex.printStackTrace(); } connection = null; } } public Book getBook(String bookId) { Book book = null; try { connect(); PreparedStatement statement = connection.prepareStatement("SELECT * FROM bookcatalog WHERE bookid = ?"); statement.setString(1, bookId); ResultSet result = statement.executeQuery(); if (result.next()) book = createBook(result); statement.close(); } catch (SQLException ex) { ex.printStackTrace(); } return book; } public Book[] getBooks() { Book [] bookArray = null; try { connect(); Statement statement = connection.createStatement(); ResultSet result = statement.executeQuery("SELECT * FROM bookcatalog ORDER BY datacreateddate DESC"); bookArray = createBooks(result); statement.close(); } catch (SQLException ex) { ex.printStackTrace(); } return bookArray; } public synchronized Book addBook(Book book) { try { connect(); String bookId = book.getBookId(); if (bookId == null || bookId.length() == 0 || getBook(bookId) != null) bookId = createUniqueBookId(); PreparedStatement statement = connection.prepareStatement("INSERT INTO bookcatalog (bookid,title,author,translator,publisher,publicationdate,code,status,keyword,memo,datacreator,datacreateddate) VALUES (?,?,?,?,?,to_date(?,'YYYY-MM-DD'),?,?,?,?,?,to_timestamp(?,'YYYY-MM-DD HH24:MI:SS'))"); statement.setString(1, bookId); statement.setString(2, book.getTitle()); statement.setString(3, book.getAuthor()); statement.setString(4, book.getTranslator()); statement.setString(5, book.getPublisher()); statement.setString(6, book.getPublicationDate()); statement.setString(7, book.getCode()); statement.setString(8, book.getStatus()); statement.setString(9, book.getKeyword()); statement.setString(10, book.getMemo()); statement.setString(11, book.getDataCreator()); statement.setString(12, book.getDataCreatedDate()); int result = statement.executeUpdate(); statement.close(); return getBook(bookId); } catch (SQLException ex) { ex.printStackTrace(); } return null; } public void deleteBook(String bookId) { try { connect(); PreparedStatement statement = connection.prepareStatement("DELETE FROM bookcatalog WHERE bookid = ?"); statement.setString(1, bookId); int result = statement.executeUpdate(); statement.close(); } catch (SQLException ex) { ex.printStackTrace(); } } public Book[] searchBooks(String word) { Book [] bookArray = null; try { connect(); PreparedStatement statement = connection.prepareStatement("SELECT * FROM bookcatalog WHERE bookid LIKE ? OR UPPER(title) LIKE ? OR UPPER(author) LIKE ? OR UPPER(translator) LIKE ? OR UPPER(publisher) LIKE ? OR UPPER(code) LIKE ? OR UPPER(status) LIKE ? OR UPPER(keyword) LIKE ? OR UPPER(memo) LIKE ? OR UPPER(datacreator) LIKE ? ORDER BY datacreateddate DESC"); String pattern = "%" + word.toUpperCase() + "%"; for (int i = 1; i <= 10; i++) statement.setString(i, pattern); ResultSet result = statement.executeQuery(); bookArray = createBooks(result); statement.close(); } catch (SQLException ex) { ex.printStackTrace(); } return bookArray; } protected Book createBook(ResultSet result) throws SQLException { Book book = new Book(); book.setBookId(result.getString("bookid")); book.setTitle(result.getString("title")); book.setAuthor(result.getString("author")); book.setTranslator(result.getString("translator")); book.setPublicationDate(result.getTimestamp("publicationdate").toString().substring(0,10)); book.setPublisher(result.getString("publisher")); book.setCode(result.getString("code")); book.setStatus(result.getString("status")); book.setKeyword(result.getString("keyword")); book.setMemo(result.getString("memo")); book.setDataCreatedDate(result.getTimestamp("datacreateddate").toString().substring(0,16)); book.setDataCreator(result.getString("datacreator")); return book; } protected Book [] createBooks(ResultSet result) throws SQLException { Vector books = new Vector(); while (result.next()) books.add(createBook(result)); Book [] bookArray = new Book[books.size()]; books.toArray(bookArray); return bookArray; }}
上面是写的关于数据库插入和删除的程序，这个程序是一个图书管理的程序，但是从java却不能访问这个数据库。我已经建立好这个数据库了，在用DBviewer也能进行访问，但是程序却无法访问，我这个是一个web程序，当按下inedx.html文件中的图书一览的这个功能的时候出现了一下错误。
type 例外报告
信息
明 The server encountered an internal error () that prevented it from fulfilling this request.
例外
org.apache.jasper.JasperException: javax.servlet.ServletException: java.lang.NoClassDefFoundError: org/postgresql/Driver
org.apache.jasper.servlet.JspServletWrapper.handleJspException(JspServletWrapper.java:548)
org.apache.jasper.servlet.JspServletWrapper.service(JspServletWrapper.java:456)
org.apache.jasper.servlet.JspServlet.serviceJspFile(JspServlet.java:389)
org.apache.jasper.servlet.JspServlet.service(JspServlet.java:333)
javax.servlet.http.HttpServlet.service(HttpServlet.java:722)
原因
javax.servlet.ServletException: java.lang.NoClassDefFoundError: org/postgresql/Driver
org.apache.jasper.runtime.PageContextImpl.doHandlePageException(PageContextImpl.java:911)
org.apache.jasper.runtime.PageContextImpl.handlePageException(PageContextImpl.java:840)
org.apache.jsp.list_jsp._jspService(list_jsp.java:111)
org.apache.jasper.runtime.HttpJspBase.service(HttpJspBase.java:70)
javax.servlet.http.HttpServlet.service(HttpServlet.java:722)
org.apache.jasper.servlet.JspServletWrapper.service(JspServletWrapper.java:433)
org.apache.jasper.servlet.JspServlet.serviceJspFile(JspServlet.java:389)
org.apache.jasper.servlet.JspServlet.service(JspServlet.java:333)
javax.servlet.http.HttpServlet.service(HttpServlet.java:722)
原因
java.lang.NoClassDefFoundError: org/postgresql/Driver
jp.bcat.DatabaseBookCatalog.connect(DatabaseBookCatalog.java:23)
jp.bcat.DatabaseBookCatalog.<init>(DatabaseBookCatalog.java:13)
jp.bcat.BookCatalog.getInstance(BookCatalog.java:27)
org.apache.jsp.list_jsp._jspService(list_jsp.java:69)
org.apache.jasper.runtime.HttpJspBase.service(HttpJspBase.java:70)
javax.servlet.http.HttpServlet.service(HttpServlet.java:722)
org.apache.jasper.servlet.JspServletWrapper.service(JspServletWrapper.java:433)
org.apache.jasper.servlet.JspServlet.serviceJspFile(JspServlet.java:389)
org.apache.jasper.servlet.JspServlet.service(JspServlet.java:333)
javax.servlet.http.HttpServlet.service(HttpServlet.java:722)
恳求高手们的帮助，谢谢大家了。
[解决办法]
是project找不到postgres的驱动jar包
[解决办法]
在WEB—INF的lib的目录中加入postgreSQL的jar的包就能解决了，postgreSQL的下载地址是http://jdbc.postgresql.org/download.html
我的异常网推荐解决方案：The server encountered an internal error () that prevented it from fulfilling this request.,http://www.myexception.cn/java-web/317.html