用java編寫菱形

for(i=1;i<=4;i++)

{

這個小的for是打印每壹行前邊的空格

for(j=1;j<=4-i;j++)

System.out.print(" ");

這個是打印星星的

for(j=1;j<=2*i-1;j++)

System.out.print("*");

這個是打印完壹行的換行

System.out.println("");

}

下邊的是壹樣的 ?只不過每壹行的空格和星星數 ? 和上邊是翻過來的

for(i=1;i<=3;i++)

{

for(j=1;j<=i;j++)

System.out.print(" ");

for(j=1;j<=7-2*i;j++)

System.out.print("*");

System.out.println("");

}

java.sql.SQLException: 無效的列索引

無效的列索引

at oracle.jdbc.driver.DatabaseError.throwSqlException(DatabaseError.java:111)

at oracle.jdbc.driver.DatabaseError.throwSqlException(DatabaseError.java:145)

at oracle.jdbc.driver.DatabaseError.throwSqlException(DatabaseError.java:207)

atoracle.jdbc.driver.OraclePreparedStatement.setStringInternal(OraclePreparedStatement.java:5328)

atoracle.jdbc.driver.OraclePreparedStatement.setString(OraclePreparedStatement.java:5320)

at untitled5.addreader1.validID(addreader1.java:128)

at untitled5.addreader1.jButton1_actionPerformed(addreader1.java:97)

at untitled5.addreader1_jButton1_actionAdapter.actionPerformed(addreader1.java:175)

at javax.swing.AbstractButton.fireActionPerformed(Unknown Source)

at javax.swing.AbstractButton$Handler.actionPerformed(Unknown Source)

at javax.swing.DefaultButtonModel.fireActionPerformed(Unknown Source)

at javax.swing.DefaultButtonModel.setPressed(Unknown Source)

at javax.swing.plaf.basic.BasicButtonListener.mouseReleased(Unknown Source)

at java.awt.Component.processMouseEvent(Unknown Source)

at javax.swing.JComponent.processMouseEvent(Unknown Source)

at java.awt.Component.processEvent(Unknown Source)

at java.awt.Container.processEvent(Unknown Source)

at java.awt.Component.dispatchEventImpl(Unknown Source)

at java.awt.Container.dispatchEventImpl(Unknown Source)

at java.awt.Component.dispatchEvent(Unknown Source)

at java.awt.LightweightDispatcher.retargetMouseEvent(Unknown Source)

at java.awt.LightweightDispatcher.processMouseEvent(Unknown Source

at java.awt.LightweightDispatcher.dispatchEvent(Unknown Source)

at java.awt.Container.dispatchEventImpl(Unknown Source)

at java.awt.Window.dispatchEventImpl(Unknown Source)

at java.awt.Component.dispatchEvent(Unknown Source)

at java.awt.EventQueue.dispatchEvent(Unknown Source)

at java.awt.EventDispatchThread.pumpOneEventForFilters(Unknown Source)

at java.awt.EventDispatchThread.pumpEventsForFilter(Unknown Source)

at java.awt.EventDispatchThread.pumpEventsForHierarchy(Unknown Source)

at java.awt.EventDispatchThread.pumpEvents(Unknown Source)

at java.awt.EventDispatchThread.pumpEvents(Unknown Source)

at java.awt.EventDispatchThread.run(Unknown Source)

代碼：String driverName = "oracle.jdbc.OracleDriver";

Driver driver = (Driver) Class.forName(driverName).newInstance();

//連接數據庫

Connection con = DriverManager.getConnection(

"jdbc:oracle:thin:@LONG:1521:orcl", "sysman", "tongfang");

PreparedStatement pstmt = con.prepareStatement(

" insert into reader values(?)");

pstmt.setString(1, str1);

pstmt.setString(2,str2);

pstmt.setString(3,str3);

pstmt.setString(4,str4);

ResultSet res = pstmt.executeQuery();