当我在网站上搜索有关如何正确显示RTL文本时，我发现了有关this post库的ICU，实际上，我以前没有任何使用它的经验。而且几乎没有清晰的在线资源。
这里的任何人都有使用它的先前经验吗？或至少告诉我要获得想要的东西我必须寻找什么？
最佳答案
嗨，阿德姆(Adham)，我对ICU4J的经验很少，我试图读取LTR阿拉伯文本并将其转换为RTL文本
我将数字从英语更改为阿拉伯数字，并将对齐方式设置为RTL。这是一个简单的代码，可以完成这项工作，希望我的一点经验对您有所帮助，这是ICU4J站点中的demos
PdfReader reader = new PdfReader(INPUTFILE);
String txt=PdfTextExtractor.getTextFromPage(reader, 1);
BiDiClass bidiClass = new BiDiClass();
String arabicNumber = bidiClass.englishToArabicNumber(txt);
String out=bidiClass.makeLineLogicalOrder(arabicNumber, true);
System.out.println(out);
这是BiDiClass
import com.ibm.icu.text.Bidi;
import com.ibm.icu.text.Normalizer;
//Editor : Ibraheem Osama Mohamed
/**
* This class is an implementation the the ICU4J class. TextNormalize
* will call this only if the ICU4J library exists in the classpath.
* @author <a href="mailto:[email protected]">Brian Carrier</a>
* @version $Revision: 1.0 $
*/
public class BiDiClass {
private static final String REPLACE_CHARS = "0123456789.";
private Bidi bidi;
private StringBuilder sb = new StringBuilder();
/**
* Constructor.
*/
public BiDiClass()
{
bidi = new Bidi();
/* We do not use bidi.setInverse() because that uses
* Bidi.REORDER_INVERSE_NUMBERS_AS_L, which caused problems
* in some test files. For example, a file had a line of:
* 0 1 / ARABIC
* and the 0 and 1 were reversed in the end result.
* REORDER_INVERSE_LIKE_DIRECT is the inverse Bidi mode
* that more closely reflects the Unicode spec.
*/
bidi.setReorderingMode(Bidi.REORDER_INVERSE_LIKE_DIRECT);
}
/**
* Takes a line of text in presentation order and converts it to logical order.
* @see TextNormalize.makeLineLogicalOrder(String, boolean)
*
* @param str String to convert
* @param isRtlDominant RTL (right-to-left) will be the dominant text direction
* @return The converted string
*/
public String makeLineLogicalOrder(String str, boolean isRtlDominant)
{
bidi.setPara(str, isRtlDominant?Bidi.RTL:Bidi.LTR, null);
/* Set the mirror flag so that parentheses and other mirror symbols
* are properly reversed, when needed. With this removed, lines
* such as (CBA) in the PDF file will come out like )ABC( in logical
* order.
*/
return bidi.writeReordered(Bidi.DO_MIRRORING);
}
//algorithm to change form English number to Arabic number
public String englishToArabicNumber(String string){
char[] ch=string.toCharArray();
for (char c : ch) {
if (REPLACE_CHARS.contains(String.valueOf(c))) {
c = (char) ('\u0660' - '0' + c);
}
sb.append(c);
}
return sb.toString();
}
/**
* Normalize presentation forms of characters to the separate parts.
* @see TextNormalize.normalizePres(String)
*
* @param str String to normalize
* @return Normalized form
*/
public String normalizePres(String str)
{
StringBuilder builder = null;
int p = 0;
int q = 0;
int strLength = str.length();
for (; q < strLength; q++) /* >>>*/
{
// We only normalize if the codepoint is in a given range.
// Otherwise, NFKC converts too many things that would cause
// confusion. For example, it converts the micro symbol in
// extended Latin to the value in the Greek script. We normalize
// the Unicode Alphabetic and Arabic A&B Presentation forms.
char c = str.charAt(q);
if ((0xFB00 <= c && c <= 0xFDFF) || (0xFE70 <= c && c <= 0xFEFF))/* >>>*/
{
if (builder == null) {
builder = new StringBuilder(strLength * 2);
}
builder.append(str.substring(p, q));
// Some fonts map U+FDF2 differently than the Unicode spec.
// They add an extra U+0627 character to compensate.
// This removes the extra character for those fonts.
if(c == 0xFDF2 && q > 0 && (str.charAt(q-1) == 0x0627 || str.charAt(q-1) == 0xFE8D))
{
builder.append("\u0644\u0644\u0647");
}
else
{
// Trim because some decompositions have an extra space,
// such as U+FC5E
builder.append(
Normalizer.normalize(c, Normalizer.NFKC).trim());
}
p = q + 1;
}
}
if (builder == null) {
return str;
} else {
builder.append(str.substring(p, q));
return builder.toString();
}
}
/**
* Decomposes Diacritic characters to their combining forms.
*
* @param str String to be Normalized
* @return A Normalized String
*/
public String normalizeDiac(String str)
{
StringBuilder retStr = new StringBuilder();
int strLength = str.length();
for (int i = 0; i < strLength; i++) /* >>>*/
{
char c = str.charAt(i);
if(Character.getType(c) == Character.NON_SPACING_MARK
|| Character.getType(c) == Character.MODIFIER_SYMBOL
|| Character.getType(c) == Character.MODIFIER_LETTER)
{
/*
* Trim because some decompositions have an extra space, such as
* U+00B4
*/
retStr.append(Normalizer.normalize(c, Normalizer.NFKC).trim());
}
else
{
retStr.append(str.charAt(i));
}
}
return retStr.toString();
}
}