Should I completely avoid the use of those methods? I wouldn't say "avoid" them. I'd say that if you think you need them, you're probably doing something wrong. Component sizes are determined in context. For example, Text component sizes are determined by the number of rows and columns you specify, combined with the font you may have chosen. Your button and label size will be the size of the graphic, if you set one, or the space needed to display the text you set. Each component has a natural size, and the layout managers will use those to lay everything out without you needing to specify sizes. The main exception is the JScrollPane, which has a size independent of whatever it contains. For those, I will sometimes call setSize(), and let that size determine the initial window size, by calling JFrame.pack(). Usually, I will let the window size determine the JScrollPane size. The user will determine the size of the window. Many layout managers ignore the sizes you set anyway, so they often don't do much good.

定义这些方法是有原因的。那么什么时候使用它们呢?在什么情况下?为了什么目的? 我相信添加它们是为了给布局管理器提供提示。它们可能是由于历史原因而编写的，因为布局管理器是新的，人们并不完全信任它们。我认识一些开发人员，他们避免使用布局管理器，并手动放置所有东西，只是因为他们不想费心学习新的范例。这是个糟糕的主意。

使用这些方法的负面后果究竟是什么?(我只能考虑在不同屏幕分辨率的系统之间增加可移植性)。 它们是无效的，而且会产生糟糕的布局，物体会被挤压或拉伸到非自然的大小。而且布局会很脆弱。更改窗口大小有时会破坏布局，并将内容放在错误的位置。

I don't think any LayoutManager can exactly satisfy all desired layout needs. Do I really need to implement a new LayoutManager for every little variation on my layout ? You shouldn't "implement" a new LayoutManager. You should instantiate existing ones. I often use several layout managers in a single window. Each JPanel will have its own layout manager. Some people balk at nested layouts, because they're hard to maintain. When I use them, I give each one its own creation method to make it easier to see what each one does. But I never "implement" a layout manager. I just instantiate them.

如果4的答案是“是”，这是否会导致LayoutManager类的激增，从而变得难以维护? 如果你正在为布局中的轻微变化实现新的布局管理器类，那么你使用它们是错误的。如果你只是实现新的布局管理器，你可能做错了什么。我唯一一次扩展LayoutManager类，是向JScrollPane添加缩放滑块。

In a situation where I need to define proportions between children of a Component (eg, child1 should use 10% of space, child2 40% ,child3 50%), is it possible to achieve that without implementing a custom LayoutManager? The JSplitPane has a way of specifying the percentage each component should get. The divider is movable by default, but you can turn that off if you want. I don't use that feature much. I usually have some components that take up a set size, and the rest of the space is taken up by a scroll pane. The scroll pane size will adjust with the window size. If you have two scroll panes side by side, you can put them in a JSplitPane and specify the percentage of new space given to each one as the user expands and contracts the windows.

Should I completely avoid the use of those methods? Yes for application code. The methods have been defined for a reason. So when should I use them? In which context? For what purposes? I don't know, personally I think of it as an API design accident. Slightly forced by compound components having special ideas about child sizes. "Slightly", because they should have implemented their needs with a custom LayoutManager. What exactly are the negative consequences of using those methods? (I can only think adding portability between systems with different screen resolution.) Some (incomplete, and unfortunately the links are broken due to migration of SwingLabs to java.net) technical reasons are for instance mentioned in the Rules (hehe) or in the link @bendicott found in his/her comment to my answer. Socially, posing tons of work onto your unfortunate fellow who has to maintain the code and has to track down a broken layout. I don't think any LayoutManager can exactly satisfy all desired layout needs. Do I really need to implement a new LayoutManager for every little variation on my layout? Yes, there are LayoutManagers powerful enough to satisfy a very good approximation to "all layout needs". The big three are JGoodies FormLayout, MigLayout, DesignGridLayout. So no, in practice, you rarely write LayoutManagers except for simple highly specialized environments. If the answer to 4 is "yes", won't this lead to a proliferation of LayoutManager classes which will become difficult to maintain? (The answer to 4 is "no".) In a situation where I need to define proportions between children of a Component (for example, child 1 should use 10% of space, child 2 40%, child 3 50%), is it possible to achieve that without implementing a custom LayoutManager? Any of the Big-Three can, can't even GridBag (never bothered to really master, too much trouble for too little power).

如果你在Java Swing的布局上遇到了麻烦，那么我可以强烈推荐由Karsten Lentzsch免费提供的JGoodies FormLayout，它是Forms免费软件库的一部分。

这个非常流行的布局管理器非常灵活，可以开发非常精致的Java ui。

您将在这里找到Karsten的文档，以及eclipse的一些相当不错的文档。

我应该完全避免使用这些方法吗?

不，没有正式的证据表明不允许调用或重写这些方法。事实上，Oracle说这些方法是用来给出大小提示的:http://docs.oracle.com/javase/tutorial/uiswing/layout/using.html#sizealignment。

在扩展Swing组件时(而不是在自定义组件实例上调用方法)，它们也可能被重写(这是Swing的最佳实践)。

最重要的是，无论如何指定组件的大小，都要确保组件的容器使用的布局管理器符合所请求的组件大小。

定义这些方法是有原因的。那么什么时候使用它们呢? 在什么情况下?为了什么目的?

当你需要为容器布局管理器提供自定义大小提示时，组件将被很好地布局

使用这些方法的负面后果究竟是什么?(我 只能想着在不同的系统之间添加可移植性 屏幕分辨率)。

Many layout managers do not pay attention to a component's requested maximum size. However, BoxLayout and SpringLayout do. Furthermore, GroupLayout provides the ability to set the minimum, preferred or maximum size explicitly, without touching the component. Make sure that you really need to set the component's exact size. Each Swing component has a different preferred size, depending on the font it uses and the look and feel. Thus having a set size might produce varied looks of the UI on different Systems sometimes problems can be encountered with GridBagLayout and text fields, wherein if the size of the container is smaller than the preferred size, the minimum size gets used, which can cause text fields to shrink quite substantially. JFrame does not enforce overriden getMinimumSize() only calling setMinimumSize(..) on its works

我认为任何LayoutManager都不能完全满足所有所需的布局 的需求。我真的需要实现一个新的LayoutManager每个 我的布局有点变化?

如果你说的实现是指使用，那么是的。不是一个LayoutManager可以处理所有的事情，每个LayoutManager都有它的优点和缺点，因此每个LayoutManager都可以一起使用来生成最终的布局。

参考:

http://docs.oracle.com/javase/tutorial/uiswing/layout/problems.html

以下是一些启发:

Don't use set[Preferred|Maximum|Minimum]Size() when you really mean to override get[Preferred|Maximum|Minimum]Size(), as might be done in creating your own component, shown here. Don't use set[Preferred|Maximum|Minimum]Size() when you could rely on a component's carefully overridden getPreferred|Maximum|Minimum]Size, as shown here and below. Do use set[Preferred|Maximum|Minimum]Size() to derive post-validate() geometry, as shown below and here. If a component has no preferred size, e.g. JDesktopPane, you may have to size the container, after invoking pack(), but any such choice is arbitrary. A comment may help clarify the intent. Consider alternate or custom layouts when you find that you would have to loop through many components to obtain derived sizes, as mentioned in these comments.

import java.awt.Component;
import java.awt.Dimension;
import java.awt.EventQueue;
import java.awt.GridLayout;
import java.awt.KeyboardFocusManager;
import java.beans.PropertyChangeEvent;
import java.beans.PropertyChangeListener;
import java.util.ArrayList;
import java.util.List;
import javax.swing.JComponent;
import javax.swing.JDesktopPane;
import javax.swing.JFrame;
import javax.swing.JInternalFrame;
import javax.swing.JLabel;
import javax.swing.JPanel;
import javax.swing.JScrollPane;
import javax.swing.JTextField;
import javax.swing.SwingUtilities;

/**
 * @see https://stackoverflow.com/questions/7229226
 * @see https://stackoverflow.com/questions/7228843
 */
public class DesignTest {

    private List<JTextField> list = new ArrayList<JTextField>();
    private JPanel panel = new JPanel();
    private JScrollPane sp = new JScrollPane(panel);

    public static void main(String args[]) {
        EventQueue.invokeLater(new Runnable() {

            @Override
            public void run() {
                DesignTest id = new DesignTest();
                id.create("My Project");
            }
        });
    }

    private void addField(String name) {
        JTextField jtf = new JTextField(16);
        panel.add(new JLabel(name, JLabel.LEFT));
        panel.add(jtf);
        list.add(jtf);
    }

    private void create(String strProjectName) {
        panel.setLayout(new GridLayout(0, 1));
        addField("First Name:");
        addField("Last Name:");
        addField("Address:");
        addField("City:");
        addField("Zip Code:");
        addField("Phone:");
        addField("Email Id:");
        KeyboardFocusManager.getCurrentKeyboardFocusManager()
            .addPropertyChangeListener("permanentFocusOwner",
            new FocusDrivenScroller(panel));
        // Show half the fields
        sp.setVerticalScrollBarPolicy(JScrollPane.VERTICAL_SCROLLBAR_ALWAYS);
        sp.validate();
        Dimension d = sp.getPreferredSize();
        d.setSize(d.width, d.height / 2);
        sp.setPreferredSize(d);

        JInternalFrame internaFrame = new JInternalFrame();
        internaFrame.add(sp);
        internaFrame.pack();
        internaFrame.setVisible(true);

        JDesktopPane desktopPane = new JDesktopPane();
        desktopPane.add(internaFrame);

        JFrame frmtest = new JFrame();
        frmtest.setDefaultCloseOperation(JFrame.EXIT_ON_CLOSE);
        frmtest.add(desktopPane);
        frmtest.pack();
        // User's preference should be read from java.util.prefs.Preferences
        frmtest.setSize(400, 300);
        frmtest.setLocationRelativeTo(null);
        frmtest.setVisible(true);
        list.get(0).requestFocusInWindow();
    }

    private static class FocusDrivenScroller implements PropertyChangeListener {

        private JComponent parent;

        public FocusDrivenScroller(JComponent parent) {
            this.parent = parent;
        }

        @Override
        public void propertyChange(PropertyChangeEvent evt) {
            Component focused = (Component) evt.getNewValue();
            if (focused != null
                && SwingUtilities.isDescendingFrom(focused, parent)) {
                parent.scrollRectToVisible(focused.getBounds());
            }
        }
    }
}

在这种情况下，我需要定义一个组件的孩子之间的比例(孩子1应该使用10%的空间，孩子2 40%，孩子3 50%)，是否有可能在不实现自定义布局管理器的情况下实现?

也许GridBagLayout可以满足你的需求。除此之外，网络上有大量的布局管理器，我打赌有一个符合你的要求。