package com.jsql.view.swing.util;
   
   import javax.swing.*;
   import javax.swing.border.Border;
   import javax.swing.plaf.basic.BasicSplitPaneDivider;
   import javax.swing.plaf.basic.BasicSplitPaneUI;
   import java.awt.*;
   
   public class JSplitPaneWithZeroSizeDivider extends JSplitPane {
  
      private static final int DIVIDER_DRAG_OFFSET = 4;
  
      public JSplitPaneWithZeroSizeDivider(int i) {
          super(i);
          this.setDividerSize(1);
          this.setContinuousLayout(true);
      }
  
      @Override
      public void doLayout() {
          super.doLayout();
  
          // increase divider width or height
          BasicSplitPaneDivider divider = ((BasicSplitPaneUI) this.getUI()).getDivider();
          Rectangle bounds = divider.getBounds();
          int dividerDragSize = 9;
          if (this.orientation == JSplitPane.HORIZONTAL_SPLIT) {
              bounds.x -= JSplitPaneWithZeroSizeDivider.DIVIDER_DRAG_OFFSET;
              bounds.width = dividerDragSize;
          } else {
              bounds.y -= JSplitPaneWithZeroSizeDivider.DIVIDER_DRAG_OFFSET;
              bounds.height = dividerDragSize;
          }
          divider.setBounds(bounds);
      }
  
      @Override
      public void updateUI() {
          this.setUI(new SplitPaneWithZeroSizeDividerUI());
          this.revalidate();
      }
  
      private static class SplitPaneWithZeroSizeDividerUI extends BasicSplitPaneUI {
  
          @Override
          public BasicSplitPaneDivider createDefaultDivider() {
              return new ZeroSizeDivider(this);
          }
  
          @Override
          protected void installDefaults() {
              super.installDefaults();
  
              // make sure that divider is first component (and can overlap left/right components)
              if (this.splitPane.getComponent(0) != this.divider) {
                  this.splitPane.setLeftComponent(this.splitPane.getLeftComponent());
                  this.splitPane.setRightComponent(this.splitPane.getRightComponent());
              }
          }
      }
  
      private static class ZeroSizeDivider extends BasicSplitPaneDivider {
  
          public ZeroSizeDivider(BasicSplitPaneUI ui) {
              super(ui);
              super.setBorder(null);
              this.setBackground(UIManager.getColor("controlShadow"));
          }
  
          @Override
          public void setBorder(Border border) {
              // ignore
          }
  
          @Override
          public void paint(Graphics g) {
              g.setColor(this.getBackground());
              if (this.orientation == JSplitPane.HORIZONTAL_SPLIT) {
                  g.drawLine(JSplitPaneWithZeroSizeDivider.DIVIDER_DRAG_OFFSET, 0, JSplitPaneWithZeroSizeDivider.DIVIDER_DRAG_OFFSET, this.getHeight() - 1);
              } else {
                  g.drawLine(0, JSplitPaneWithZeroSizeDivider.DIVIDER_DRAG_OFFSET, this.getWidth() - 1, JSplitPaneWithZeroSizeDivider.DIVIDER_DRAG_OFFSET);
              }
          }
  
          @Override
          protected void dragDividerTo(int location) {
              super.dragDividerTo(location + JSplitPaneWithZeroSizeDivider.DIVIDER_DRAG_OFFSET);
          }
  
          @Override
          protected void finishDraggingTo(int location) {
              super.finishDraggingTo(location + JSplitPaneWithZeroSizeDivider.DIVIDER_DRAG_OFFSET);
          }
      }
  }