关于Exception in thread "main" java问题.lang.NullPointerException

tobyluo 2010-01-11 06:21:21
编译吧不报错 但执行 就会 出现 以下 内容
--------------------Configuration: <Default>--------------------
Exception in thread "main" java.lang.NullPointerException
at java.util.Hashtable.put(Hashtable.java:399)
at java.awt.GridBagLayout.setConstraints(GridBagLayout.java:482)
at customerInfor.<init>(customerInfor.java:60)
at customerInfor.main(customerInfor.java:172)

Process completed.
源代码 是
// 客户信息
import java.awt.*;
import java.awt.event.*;
import javax.swing.*;
import javax.swing.event.*;
public class customerInfor extends JFrame
{
JButton SaveGroupInformationButton,DeleteInfoButton;
JLabel customerIDJlabel,customerNameJlabel,customerPhoneJlabel,
contactMobilePhoneJlabel,contactNameJlabel,contactEmailJlabel,contactFaxJlable,
contactAdressJlabel,custactpostcodeJlabel;
JTextField customerIdField,customerNameField,customerPhomefield,customerMobiPhonefield,
costactNameField,costactEmailField,contactFaxfield,contactAdressField,cunstactPosstcodeField;

GridBagLayout g1;
GridBagConstraints gbc;
public customerInfor(){
super("客户信息");
Container c=this.getContentPane();
customerIDJlabel=new JLabel("客户 ID");
customerIdField=new JTextField(20);
contactNameJlabel=new JLabel("客户姓名");
customerNameField=new JTextField(20);
contactMobilePhoneJlabel=new JLabel("手机");
customerMobiPhonefield=new JTextField(20);
contactNameJlabel=new JLabel("联系人姓名");
costactNameField=new JTextField(20);
contactEmailJlabel=new JLabel("E-mail");
costactEmailField=new JTextField(20);
contactFaxJlable=new JLabel("传真");
contactFaxfield=new JTextField(20);
contactAdressJlabel=new JLabel("联系地址");
contactAdressField=new JTextField(20);
custactpostcodeJlabel=new JLabel("邮编");
cunstactPosstcodeField=new JTextField(20);

g1=new GridBagLayout();
gbc=new GridBagConstraints();
c.setLayout(g1);

//给限定对象gbc的参数赋值


// gbc.fill=GridBagConstraints.BOTH;
gbc.weightx=1.0;
gbc.gridx=0;
gbc.gridy=0;
g1.setConstraints(customerIDJlabel,gbc);
c.add(customerIDJlabel);

gbc.weightx=1.0;
gbc.gridx=0;
gbc.gridy=1;
g1.setConstraints(customerIdField,gbc);
c.add(customerIdField);

gbc.weightx=1.0;
gbc.gridx=0;
gbc.gridy=3;
g1.setConstraints(customerNameJlabel,gbc);
c.add(customerNameJlabel);



gbc.weightx=1.0;
gbc.gridx=0;
gbc.gridy=4;
g1.setConstraints(customerNameField,gbc);
c.add(customerNameField);

gbc.weightx=1.0;
gbc.gridx=1;
gbc.gridy=0;
g1.setConstraints(contactNameJlabel,gbc);
c.add(contactNameJlabel);

gbc.weightx=1.0;
gbc.gridx=1;
gbc.gridy=1;
g1.setConstraints(costactNameField,gbc);
c.add(costactNameField);

gbc.weightx=1.0;
gbc.gridx=1;
gbc.gridy=2;
g1.setConstraints(customerPhoneJlabel,gbc);
c.add(customerPhoneJlabel);

gbc.weightx=1.0;
gbc.gridx=1;
gbc.gridy=3;
g1.setConstraints(customerPhomefield,gbc);
c.add(customerPhomefield);

gbc.weightx=1.0;
gbc.gridx=2;
gbc.gridy=0;
g1.setConstraints(contactMobilePhoneJlabel,gbc);
c.add(contactMobilePhoneJlabel);

gbc.weightx=1.0;
gbc.gridx=2;
gbc.gridy=1;
g1.setConstraints(customerMobiPhonefield,gbc);
c.add(customerMobiPhonefield);

gbc.weightx=1.0;
gbc.gridx=2;
gbc.gridy=2;
g1.setConstraints(contactEmailJlabel,gbc);
c.add(contactEmailJlabel);

gbc.weightx=1.0;
gbc.gridx=2;
gbc.gridy=3;
g1.setConstraints(costactEmailField,gbc);
c.add(costactEmailField);

gbc.weightx=1.0;
gbc.gridx=3;
gbc.gridy=0;
g1.setConstraints(contactFaxJlable,gbc);
c.add(contactFaxJlable);

gbc.weightx=1.0;
gbc.gridx=3;
gbc.gridy=1;
g1.setConstraints(contactFaxfield,gbc);
c.add(contactFaxfield);

gbc.weightx=1.0;
gbc.gridx=3;
gbc.gridy=2;
g1.setConstraints(custactpostcodeJlabel,gbc);
c.add(custactpostcodeJlabel);

gbc.weightx=1.0;
gbc.gridx=3;
gbc.gridy=3;
g1.setConstraints(cunstactPosstcodeField,gbc);
c.add(cunstactPosstcodeField);


gbc.gridx=4;
gbc.gridy=0;
gbc.weightx=1.0;
g1.setConstraints(contactAdressJlabel,gbc);
c.add(contactAdressJlabel);

gbc.gridx=4;
gbc.gridy=1;
gbc.gridwidth=3;
g1.setConstraints(contactAdressField,gbc);
c.add(contactAdressField);





this.setSize(350,200);
this.setLocationRelativeTo(null);
// this.setDefaultCloseOperation(JFrame.EXIT_ON_CLOSE);
this.setVisible(true);





}
public static void main (String[]args)
{
new customerInfor();
}
}
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wmp88520 2010-01-17
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属性中的jlable和jtextfiled都没有实例化所以会报错，
package cn.com.test;

import java.awt.*;
import java.awt.event.*;
import javax.swing.*;
import javax.swing.event.*;

public class customerInfor extends JFrame {
JButton SaveGroupInformationButton, DeleteInfoButton;

JLabel customerIDJlabel=new JLabel(), customerNameJlabel=new JLabel(), customerPhoneJlabel=new JLabel(),
contactMobilePhoneJlabel=new JLabel(), contactNameJlabel=new JLabel(), contactEmailJlabel=new JLabel(),
contactFaxJlable=new JLabel(), contactAdressJlabel=new JLabel(), custactpostcodeJlabel=new JLabel();

JTextField customerIdField=new JTextField(), customerNameField=new JTextField(), customerPhomefield=new JTextField(),
customerMobiPhonefield=new JTextField(), costactNameField=new JTextField(), costactEmailField=new JTextField(),
contactFaxfield=new JTextField(), contactAdressField=new JTextField(), cunstactPosstcodeField=new JTextField();

GridBagLayout g1;

GridBagConstraints gbc;

public customerInfor() {
super("客户信息");
Container c = this.getContentPane();
customerIDJlabel = new JLabel("客户 ID");
customerIdField = new JTextField(20);
contactNameJlabel = new JLabel("客户姓名");
customerNameField = new JTextField(20);
contactMobilePhoneJlabel = new JLabel("手机");
customerMobiPhonefield = new JTextField(20);
contactNameJlabel = new JLabel("联系人姓名");
costactNameField = new JTextField(20);
contactEmailJlabel = new JLabel("E-mail");
costactEmailField = new JTextField(20);
contactFaxJlable = new JLabel("传真");
contactFaxfield = new JTextField(20);
contactAdressJlabel = new JLabel("联系地址");
contactAdressField = new JTextField(20);
custactpostcodeJlabel = new JLabel("邮编");
cunstactPosstcodeField = new JTextField(20);

g1 = new GridBagLayout();
gbc = new GridBagConstraints();
c.setLayout(g1);

//给限定对象gbc的参数赋值

// gbc.fill=GridBagConstraints.BOTH;
gbc.weightx = 1.0;
gbc.gridx = 0;
gbc.gridy = 0;
g1.setConstraints(customerIDJlabel, gbc);
c.add(customerIDJlabel);

gbc.weightx = 1.0;
gbc.gridx = 0;
gbc.gridy = 1;
g1.setConstraints(customerIdField, gbc);
c.add(customerIdField);
gbc.weightx = 1.0;
gbc.gridx = 0;
gbc.gridy = 3;
g1.setConstraints(customerNameJlabel, gbc);
c.add(customerNameJlabel);

gbc.weightx = 1.0;
gbc.gridx = 0;
gbc.gridy = 4;
g1.setConstraints(customerNameField, gbc);
c.add(customerNameField);

gbc.weightx = 1.0;
gbc.gridx = 1;
gbc.gridy = 0;
g1.setConstraints(contactNameJlabel, gbc);
c.add(contactNameJlabel);

gbc.weightx = 1.0;
gbc.gridx = 1;
gbc.gridy = 1;
g1.setConstraints(costactNameField, gbc);
c.add(costactNameField);

gbc.weightx = 1.0;
gbc.gridx = 1;
gbc.gridy = 2;
g1.setConstraints(customerPhoneJlabel, gbc);
c.add(customerPhoneJlabel);

gbc.weightx = 1.0;
gbc.gridx = 1;
gbc.gridy = 3;
g1.setConstraints(customerPhomefield, gbc);
c.add(customerPhomefield);

gbc.weightx = 1.0;
gbc.gridx = 2;
gbc.gridy = 0;
g1.setConstraints(contactMobilePhoneJlabel, gbc);
c.add(contactMobilePhoneJlabel);

gbc.weightx = 1.0;
gbc.gridx = 2;
gbc.gridy = 1;
g1.setConstraints(customerMobiPhonefield, gbc);
c.add(customerMobiPhonefield);

gbc.weightx = 1.0;
gbc.gridx = 2;
gbc.gridy = 2;
g1.setConstraints(contactEmailJlabel, gbc);
c.add(contactEmailJlabel);

gbc.weightx = 1.0;
gbc.gridx = 2;
gbc.gridy = 3;
g1.setConstraints(costactEmailField, gbc);
c.add(costactEmailField);

gbc.weightx = 1.0;
gbc.gridx = 3;
gbc.gridy = 0;
g1.setConstraints(contactFaxJlable, gbc);
c.add(contactFaxJlable);

gbc.weightx = 1.0;
gbc.gridx = 3;
gbc.gridy = 1;
g1.setConstraints(contactFaxfield, gbc);
c.add(contactFaxfield);

gbc.weightx = 1.0;
gbc.gridx = 3;
gbc.gridy = 2;
g1.setConstraints(custactpostcodeJlabel, gbc);
c.add(custactpostcodeJlabel);

gbc.weightx = 1.0;
gbc.gridx = 3;
gbc.gridy = 3;
g1.setConstraints(cunstactPosstcodeField, gbc);
c.add(cunstactPosstcodeField);

gbc.gridx = 4;
gbc.gridy = 0;
gbc.weightx = 1.0;
g1.setConstraints(contactAdressJlabel, gbc);
c.add(contactAdressJlabel);

gbc.gridx = 4;
gbc.gridy = 1;
gbc.gridwidth = 3;
g1.setConstraints(contactAdressField, gbc);
c.add(contactAdressField);

this.setSize(350, 200);
this.setLocationRelativeTo(null);
// this.setDefaultCloseOperation(JFrame.EXIT_ON_CLOSE);
this.setVisible(true);

}

public static void main(String[] args) {
new customerInfor();
}
}
poFate 2010-01-11
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上边的代码已经可以运行了 再找bug的时候根据它报错的行号一步步的找 细点心
at customerInfor. <init>(customerInfor.java:60) 错误在60行
at customerInfor.main(customerInfor.java:172)
poFate 2010-01-11
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import java.awt.*;

import java.awt.event.*;

import javax.swing.*;

import javax.swing.event.*;

public class customerInfor extends JFrame

{

JButton SaveGroupInformationButton,DeleteInfoButton;

JLabel customerIDJlabel,customerNameJlabel,customerPhoneJlabel,

        contactMobilePhoneJlabel,contactNameJlabel,contactEmailJlabel,contactFaxJlable,

        contactAdressJlabel,custactpostcodeJlabel;

    JTextField customerIdField,customerNameField,customerPhomefield,customerMobiPhonefield,

              costactNameField,costactEmailField,contactFaxfield,contactAdressField,cunstactPosstcodeField;



GridBagLayout g1;

GridBagConstraints  gbc;

public customerInfor(){

super("客户信息");

Container c=this.getContentPane();

customerIDJlabel=new JLabel("客户 ID");

customerIdField=new JTextField(20);

contactNameJlabel=new JLabel("客户姓名");

customerNameField=new JTextField(20);

customerPhomefield = new JTextField(20);

        contactMobilePhoneJlabel=new JLabel("手机");

        customerMobiPhonefield=new JTextField(20);

        contactNameJlabel=new JLabel("联系人姓名");

        costactNameField=new JTextField(20);

        contactEmailJlabel=new JLabel("E-mail");

        costactEmailField=new JTextField(20);

        contactFaxJlable=new JLabel("传真");

        contactFaxfield=new JTextField(20);

        contactAdressJlabel=new JLabel("联系地址");

        contactAdressField=new JTextField(20);

        custactpostcodeJlabel=new JLabel("邮编");

        cunstactPosstcodeField=new JTextField(20);

		customerNameJlabel = new JLabel("你没有初始化");

		customerPhoneJlabel = new JLabel("你没有初始化2");

g1=new GridBagLayout();

gbc=new GridBagConstraints();

c.setLayout(g1);



//给限定对象gbc的参数赋值



       

      // gbc.fill=GridBagConstraints.BOTH;

        gbc.weightx=1.0;

        gbc.gridx=0;

        gbc.gridy=0;

        g1.setConstraints(customerIDJlabel,gbc);

        c.add(customerIDJlabel);

       

        gbc.weightx=1.0;

        gbc.gridx=0;

        gbc.gridy=1;

        g1.setConstraints(customerIdField,gbc);

        c.add(customerIdField);

       

        gbc.weightx=1.0;

        gbc.gridx=0;

        gbc.gridy=3;

        g1.setConstraints(customerNameJlabel,gbc);

        c.add(customerNameJlabel);

       

       

         

        gbc.weightx=1.0;

        gbc.gridx=0;

        gbc.gridy=4;

        g1.setConstraints(customerNameField,gbc);

        c.add(customerNameField);

       

        gbc.weightx=1.0;

        gbc.gridx=1;

        gbc.gridy=0;

        g1.setConstraints(contactNameJlabel,gbc);

        c.add(contactNameJlabel);

       

        gbc.weightx=1.0;

        gbc.gridx=1;

        gbc.gridy=1;

        g1.setConstraints(costactNameField,gbc);

        c.add(costactNameField);

     

      gbc.weightx=1.0;

      gbc.gridx=1;

      gbc.gridy=2;

      g1.setConstraints(customerPhoneJlabel,gbc);

      c.add(customerPhoneJlabel);

     

      gbc.weightx=1.0;

      gbc.gridx=1;

      gbc.gridy=3;

      g1.setConstraints(customerPhomefield,gbc);

      c.add(customerPhomefield);

     

      gbc.weightx=1.0;

      gbc.gridx=2;

      gbc.gridy=0;

      g1.setConstraints(contactMobilePhoneJlabel,gbc);

      c.add(contactMobilePhoneJlabel);

     

      gbc.weightx=1.0;

      gbc.gridx=2;

      gbc.gridy=1;

      g1.setConstraints(customerMobiPhonefield,gbc);

      c.add(customerMobiPhonefield);

     

      gbc.weightx=1.0;

      gbc.gridx=2;

      gbc.gridy=2;

      g1.setConstraints(contactEmailJlabel,gbc);

      c.add(contactEmailJlabel);

     

      gbc.weightx=1.0;

      gbc.gridx=2;

      gbc.gridy=3;

      g1.setConstraints(costactEmailField,gbc);

      c.add(costactEmailField);

     

      gbc.weightx=1.0;

      gbc.gridx=3;

      gbc.gridy=0;

      g1.setConstraints(contactFaxJlable,gbc);

      c.add(contactFaxJlable);

     

      gbc.weightx=1.0;

      gbc.gridx=3;

      gbc.gridy=1;

      g1.setConstraints(contactFaxfield,gbc);

      c.add(contactFaxfield);

     

      gbc.weightx=1.0;

      gbc.gridx=3;

      gbc.gridy=2;

      g1.setConstraints(custactpostcodeJlabel,gbc);

      c.add(custactpostcodeJlabel);

     

      gbc.weightx=1.0;

      gbc.gridx=3;

      gbc.gridy=3;

      g1.setConstraints(cunstactPosstcodeField,gbc);

      c.add(cunstactPosstcodeField);

     

     

      gbc.gridx=4;

      gbc.gridy=0;

      gbc.weightx=1.0;

      g1.setConstraints(contactAdressJlabel,gbc);

      c.add(contactAdressJlabel);

     

      gbc.gridx=4;

      gbc.gridy=1;

      gbc.gridwidth=3;

      g1.setConstraints(contactAdressField,gbc);

      c.add(contactAdressField);

      this.setSize(350,200);

      this.setLocationRelativeTo(null);

      // this.setDefaultCloseOperation(JFrame.EXIT_ON_CLOSE);

      this.setVisible(true);

     

     

       

     

     

}

public static void main (String[]args)

    {

    new customerInfor();

    }

}

customerNameJlabel 你没有初始化
customerPhoneJlabel 你没有初始化2
customerPhomefield 没有初始化
bolink5 2010-01-11
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开发也有几年了，但还没怎么用过swing
说下空指向的一般解决方法
首先你找到报错的哪行代码，先看看这行代码中总共有几个对象，然后进行一一排除，如此，就可以解决问题。
在开发中，空指向是很普遍的问题。
chenyong0214 2010-01-11
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customerNameJlabel没有初始化，必然NULL pointer
huntor 2010-01-11
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customerNameJlabel 没有初始化
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