Here you can find the source of setUIManagerFont(int fontSize)
public static void setUIManagerFont(int fontSize)
//package com.java2s; // modify it under the terms of the GNU General Public License import java.awt.Font; import java.util.Iterator; import java.util.Set; import javax.swing.UIDefaults; import javax.swing.UIManager; import javax.swing.plaf.FontUIResource; public class Main { public static void setUIManagerFont(int fontSize) { // Method Instances Object uiObject;/*w w w . j a v a2 s .c o m*/ Font uiManagerFont; UIDefaults uiDefaults; // Setup uiObject = UIManager.get("Label.font"); if (uiObject != null && uiObject instanceof Font) uiManagerFont = (Font) uiObject; else return; if (uiManagerFont.getSize() == fontSize) return; // Collect the UI Manager keys that are fonts // and update them to the new font size. uiDefaults = UIManager.getLookAndFeelDefaults(); Set<Object> hash = uiDefaults.keySet(); Iterator<Object> iterator = hash.iterator(); while (iterator.hasNext()) { Object curObj = iterator.next(); // System.out.println("LindyFrame_Utils setUIManager() " + curObj.toString()); if (curObj.toString().indexOf("font") != -1) { /* System.out.println("LindyFrmae_Utils setUIManager() " + curObj + "\n" + "Font Name: " + uiManagerFont.getFontName() + "\n" + "Name: " + uiManagerFont.getName() + "\n" + "Style: " + uiManagerFont.getStyle() + "\n" + "Size: " + fontSize); */ if (fontSize > 16) UIManager.put(curObj, new FontUIResource(uiManagerFont.getName(), Font.PLAIN, fontSize)); else UIManager.put(curObj, new FontUIResource(uiManagerFont.getName(), uiManagerFont.getStyle(), fontSize)); } } } }