JTextField public JTextField(int columns) Constructs a new empty TextField with the specified number of columns. A default model is created and the initial string is set to null. Parameters: columns - the number of columns to use to calculate the preferred width; if columns is set to zero, the preferred width will be whatever naturally results from the component implementation
参数 是长度吧
public JTextField(int columns)
Constructs a new empty TextField with the specified number of columns. A default model is created and the initial string is set to null. Parameters:
columns - the number of columns to use to calculate the preferred width; if columns is set to zero, the preferred width will be whatever naturally results from the component implementation