GrouopLayout这个布局我不是很懂，求帮助

各位英雄好汉，能帮我分析一下这段代码吗？

GroupLayout layout = new GroupLayout(this);
        this.setLayout(layout);
        layout.setHorizontalGroup(layout.createParallelGroup(
                GroupLayout.Alignment.LEADING).addGap(0, 800,
                Short.MAX_VALUE).addGroup(
                layout.createParallelGroup(
                        GroupLayout.Alignment.LEADING).addGroup(
                        layout.createSequentialGroup().addGap(0, 0,
                                Short.MAX_VALUE).addComponent(jPanel4,
                                GroupLayout.PREFERRED_SIZE, 795,
                                GroupLayout.PREFERRED_SIZE).addGap(
                                0, 0, Short.MAX_VALUE))));
        layout.setVerticalGroup(layout.createParallelGroup(
                GroupLayout.Alignment.LEADING).addGap(0, 460,
                Short.MAX_VALUE).addGroup(
                layout.createParallelGroup(
                        GroupLayout.Alignment.LEADING).addGroup(
                        layout.createSequentialGroup().addGap(0, 0,
                                Short.MAX_VALUE).addComponent(jPanel4,
                                GroupLayout.PREFERRED_SIZE, 424,
                                GroupLayout.PREFERRED_SIZE).addGap(
                                0, 0, Short.MAX_VALUE))));