先尝试编写简单的程序。你写的代码越多，你对它的理解就越好。没有人可以仅通过阅读书籍或编写代码来学习编程。编程一开始看起来很难，但最终它变成了第二天性。
永远不要记住代码。没有什么好的结果。只需了解特定类的作用，IDe 将帮助您编写方法和属性。如今，几乎所有 IDE 都具有自动完成功能。
不要为您在应用程序中看到的代码量而烦恼。其中很多是由游戏引擎自动生成的，尽管您应该了解它们的含义和作用。
举个例子，这是我制作的一个简单转换器应用程序的源代码。您可以看到这里有多少代码，但使用 Netbeans IDE 我只写了两行代码，所有其他代码都是自动生成的。
/*
* To change this template, choose Tools | Templates
* and open the template in the editor.
*/
package Home;
/**
*
* @author Windows8
*/
public class CelsiusConverterGUI extends javax.swing.JFrame {
/**
* Creates new form CelsiusConverterGUI
*/
public CelsiusConverterGUI() {
initComponents();
}
/**
* This method is called from within the constructor to initialize the form.
* WARNING: Do NOT modify this code. The content of this method is always
* regenerated by the Form Editor.
*/
@SuppressWarnings("unchecked")
// <editor-fold defaultstate="collapsed" desc="Generated Code">
private void initComponents() {
tempTextField = new javax.swing.JTextField();
celsiusLabel = new javax.swing.JLabel();
convertButton = new javax.swing.JButton();
fahrenheitLabel = new javax.swing.JLabel();
setDefaultCloseOperation(javax.swing.WindowConstants.EXIT_ON_CLOSE);
setTitle("Celsius Converter");
celsiusLabel.setText("Celsius");
convertButton.setText("Convert");
convertButton.addActionListener(new java.awt.event.ActionListener() {
public void actionPerformed(java.awt.event.ActionEvent evt) {
convertButtonActionPerformed(evt);
}
});
fahrenheitLabel.setText("Fahrenheit");
javax.swing.GroupLayout layout = new javax.swing.GroupLayout(getContentPane());
getContentPane().setLayout(layout);
layout.setHorizontalGroup(
layout.createParallelGroup(javax.swing.GroupLayout.Alignment.LEADING)
.addGroup(layout.createSequentialGroup()
.addContainerGap()
.addGroup(layout.createParallelGroup(javax.swing.GroupLayout.Alignment.LEADING)
.addGroup(layout.createSequentialGroup()
.addComponent(tempTextField, javax.swing.GroupLayout.PREFERRED_SIZE, javax.swing.GroupLayout.DEFAULT_SIZE, javax.swing.GroupLayout.PREFERRED_SIZE)
.addPreferredGap(javax.swing.LayoutStyle.ComponentPlacement.RELATED)
.addComponent(celsiusLabel))
.addGroup(layout.createSequentialGroup()
.addComponent(convertButton)
.addPreferredGap(javax.swing.LayoutStyle.ComponentPlacement.RELATED)
.addComponent(fahrenheitLabel)))
.addContainerGap(javax.swing.GroupLayout.DEFAULT_SIZE, Short.MAX_VALUE))
);
layout.linkSize(javax.swing.SwingConstants.HORIZONTAL, new java.awt.Component[] {convertButton, tempTextField});
layout.setVerticalGroup(
layout.createParallelGroup(javax.swing.GroupLayout.Alignment.LEADING)
.addGroup(layout.createSequentialGroup()
.addContainerGap()
.addGroup(layout.createParallelGroup(javax.swing.GroupLayout.Alignment.BASELINE)
.addComponent(tempTextField, javax.swing.GroupLayout.PREFERRED_SIZE, javax.swing.GroupLayout.DEFAULT_SIZE, javax.swing.GroupLayout.PREFERRED_SIZE)
.addComponent(celsiusLabel))
.addPreferredGap(javax.swing.LayoutStyle.ComponentPlacement.RELATED)
.addGroup(layout.createParallelGroup(javax.swing.GroupLayout.Alignment.BASELINE)
.addComponent(convertButton)
.addComponent(fahrenheitLabel))
.addContainerGap(javax.swing.GroupLayout.DEFAULT_SIZE, Short.MAX_VALUE))
);
pack();
}// </editor-fold>
private void convertButtonActionPerformed(java.awt.event.ActionEvent evt) {
// TODO add your handling code here:
//Parse the celsius input into double
int tmpFah = (int) ((Double.parseDouble(tempTextField.getText())) * 1.8 + 32);
fahrenheitLabel.setText(tmpFah + " Fahrenheit");
}
/**
* @param args the command line arguments
*/
public static void main(String args[]) {
/* Set the Nimbus look and feel */
//<editor-fold defaultstate="collapsed" desc=" Look and feel setting code (optional) ">
/* If Nimbus (introduced in Java SE 6) is not available, stay with the default look and feel.
* For details see http://download.oracle.com/javase/tutorial/uiswing/lookandfeel/plaf.html
*/
try {
for (javax.swing.UIManager.LookAndFeelInfo info : javax.swing.UIManager.getInstalledLookAndFeels()) {
if ("Nimbus".equals(info.getName())) {
javax.swing.UIManager.setLookAndFeel(info.getClassName());
break;
}
}
} catch (ClassNotFoundException ex) {
java.util.logging.Logger.getLogger(CelsiusConverterGUI.class.getName()).log(java.util.logging.Level.SEVERE, null, ex);
} catch (InstantiationException ex) {
java.util.logging.Logger.getLogger(CelsiusConverterGUI.class.getName()).log(java.util.logging.Level.SEVERE, null, ex);
} catch (IllegalAccessException ex) {
java.util.logging.Logger.getLogger(CelsiusConverterGUI.class.getName()).log(java.util.logging.Level.SEVERE, null, ex);
} catch (javax.swing.UnsupportedLookAndFeelException ex) {
java.util.logging.Logger.getLogger(CelsiusConverterGUI.class.getName()).log(java.util.logging.Level.SEVERE, null, ex);
}
//</editor-fold>
/* Create and display the form */
java.awt.EventQueue.invokeLater(new Runnable() {
public void run() {
new CelsiusConverterGUI().setVisible(true);
}
});
}
// Variables declaration - do not modify
private javax.swing.JLabel celsiusLabel;
private javax.swing.JButton convertButton;
private javax.swing.JLabel fahrenheitLabel;
private javax.swing.JTextField tempTextField;
// End of variables declaration
}