Erro com java netbeans

[list]Erro: java.lang.NullPointerException

java.lang.NullPointerException

at DAO.CidadeDAO.inserir(CidadeDAO.java:25)

at BO.CidadeBO.inserir(CidadeBO.java:14)

at Form.Cidade.jbSalvarActionPerformed(Cidade.java:299)

at Form.Cidade.access$200(Cidade.java:18)

at Form.Cidade$3.actionPerformed(Cidade.java:99)

at javax.swing.AbstractButton.fireActionPerformed(AbstractButton.java:1995)

at javax.swing.AbstractButton$Handler.actionPerformed(AbstractButton.java:2318)

at javax.swing.DefaultButtonModel.fireActionPerformed(DefaultButtonModel.java:387)

at javax.swing.DefaultButtonModel.setPressed(DefaultButtonModel.java:242)

at javax.swing.plaf.basic.BasicButtonListener.mouseReleased(BasicButtonListener.java:236)

at java.awt.Component.processMouseEvent(Component.java:6289)

at javax.swing.JComponent.processMouseEvent(JComponent.java:3267)

at java.awt.Component.processEvent(Component.java:6054)

at java.awt.Container.processEvent(Container.java:2041)

at java.awt.Component.dispatchEventImpl(Component.java:4652)

at java.awt.Container.dispatchEventImpl(Container.java:2099)

at java.awt.Component.dispatchEvent(Component.java:4482)

at java.awt.LightweightDispatcher.retargetMouseEvent(Container.java:4577)

at java.awt.LightweightDispatcher.processMouseEvent(Container.java:4238)

at java.awt.LightweightDispatcher.dispatchEvent(Container.java:4168)

at java.awt.Container.dispatchEventImpl(Container.java:2085)

at java.awt.Window.dispatchEventImpl(Window.java:2478)

at java.awt.Component.dispatchEvent(Component.java:4482)

at java.awt.EventQueue.dispatchEventImpl(EventQueue.java:644)

at java.awt.EventQueue.access$000(EventQueue.java:85)

at java.awt.EventQueue$1.run(EventQueue.java:603)

at java.awt.EventQueue$1.run(EventQueue.java:601)

at java.security.AccessController.doPrivileged(Native Method)

at java.security.AccessControlContext$1.doIntersectionPrivilege(AccessControlContext.java:87)

at java.security.AccessControlContext$1.doIntersectionPrivilege(AccessControlContext.java:98)

at java.awt.EventQueue$2.run(EventQueue.java:617)

at java.awt.EventQueue$2.run(EventQueue.java:615)

at java.security.AccessController.doPrivileged(Native Method)

at java.security.AccessControlContext$1.doIntersectionPrivilege(AccessControlContext.java:87)

at java.awt.EventQueue.dispatchEvent(EventQueue.java:614)

at java.awt.EventDispatchThread.pumpOneEventForFilters(EventDispatchThread.java:269)

at java.awt.EventDispatchThread.pumpEventsForFilter(EventDispatchThread.java:184)

at java.awt.EventDispatchThread.pumpEventsForHierarchy(EventDispatchThread.java:174)

at java.awt.EventDispatchThread.pumpEvents(EventDispatchThread.java:169)

at java.awt.EventDispatchThread.pumpEvents(EventDispatchThread.java:161)

at java.awt.EventDispatchThread.run(EventDispatchThread.java:122)

CONSTRUÍDO COM SUCESSO (tempo total: 20 segundos)

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sendo que o local do erro

[list]public boolean inserir(CidadeDTO cidadeDTO){

try{

Connection conn =Conexao.conectar(NomedoBanco);

String sql =“INSERT INTO “+NomedaTabela+” (cod_cidade,cidade_desc,cod_estado) VALUES (?,?,?);”;

PreparedStatement ps = conn.prepareStatement(sql);

ps.setInt(1,cidadeDTO.getCod_cidade());

ps.setString(2,cidadeDTO.getCidade_desc());

 ps.setInt(3,cidadeDTO.getEstado().getCod_estado());

ps.executeUpdate();

ps.close();

conn.close();

return true;

}catch(Exception e){

System.err.println("Erro: " + e.toString());

e.printStackTrace();

return false;

}

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