The solution adopted:
private static final String PATH_FONT_ARIALUNI = "C:\\Windows\\Fonts\\arialuni.ttf";
private static final String PATH_FONT_COUR = "C:\\Windows\\Fonts\\cour.ttf";
// FOR Chinese
BaseFont baseFont = BaseFont.createFont(PATH_FONT_ARIALUNI, BaseFont.IDENTITY_H, BaseFont.EMBEDDED);
Font font = new Font(baseFont, 6.8f);
BaseFont baseFontNormal = BaseFont.createFont(PATH_FONT_COUR, BaseFont.IDENTITY_H, BaseFont.EMBEDDED);
Font fontNormal = new Font(baseFontNormal, 6.8f);
Paragraph par = new Paragraph();
par.setLeading(9);
char[] aa = line.toCharArray();
boolean isLastChineseChar = false;
System.out.println(line);
StringBuilder newLine = new StringBuilder();
for (int j = 0; j < line.length(); j++) {
if((Character.UnicodeBlock.of(aa[j]) == Character.UnicodeBlock.CJK_UNIFIED_IDEOGRAPHS)){
if(!isLastChineseChar) {
par.add(new Phrase(newLine.toString(), fontNormal));
newLine.delete(0, newLine.length());
}
newLine.append(aa[j]);
isLastChineseChar = true;
/*System.out.println("Is CHINESE: " + aa[j]);*/
} else {
if(isLastChineseChar) {
par.add(new Phrase(newLine.toString(), font));
newLine.delete(0, newLine.length());
isLastChineseChar = false;
}
newLine.append(aa[j]);
/*System.out.println("NOT IS CHINESE: " + aa[j]);*/
}
}
if(isLastChineseChar){
par.add(new Phrase(newLine.toString(), font));
} else {
par.add(new Phrase(newLine.toString(), fontNormal));
}
if(line.contains(BREAK_PAGE)) {
document.newPage();
}
par.setAlignment(Element.ALIGN_LEFT);
document.add(par);