TTFParser.java

package com.v7lin.android.env.font;

import java.io.IOException;
import java.io.RandomAccessFile;
import java.util.HashMap;
import java.util.Map;

import android.annotation.SuppressLint;

/**
 * ttf font parser
 * 
 * @author v7lin E-mail:v7lin@qq.com
 */
@SuppressLint("UseSparseArrays")
public class TTFParser {
	public static int COPYRIGHT = 0;

	public static int FAMILY_NAME = 1;

	public static int FONT_SUBFAMILY_NAME = 2;

	public static int UNIQUE_FONT_IDENTIFIER = 3;

	public static int FULL_FONT_NAME = 4;

	public static int VERSION = 5;

	public static int POSTSCRIPT_NAME = 6;

	public static int TRADEMARK = 7;

	public static int MANUFACTURER = 8;

	public static int DESIGNER = 9;

	public static int DESCRIPTION = 10;

	public static int URL_VENDOR = 11;

	public static int URL_DESIGNER = 12;

	public static int LICENSE_DESCRIPTION = 13;

	public static int LICENSE_INFO_URL = 14;

	private Map<Integer, String> fontProperties = new HashMap<Integer, String>();

	/**
	 * 获取ttf font name
	 * 
	 * @return
	 */
	public String getFontName() {
		if (fontProperties.containsKey(FULL_FONT_NAME)) {
			return fontProperties.get(FULL_FONT_NAME);
		} else if (fontProperties.containsKey(FAMILY_NAME)) {
			return fontProperties.get(FAMILY_NAME);
		} else {
			return null;
		}

	}

	/**
	 * 获取ttf属性
	 * 
	 * @param nameID
	 *            属性标记，见静态变量
	 * 
	 * @return 属性值
	 */
	public String getFontPropertie(int nameID) {
		if (fontProperties.containsKey(nameID)) {
			return fontProperties.get(nameID);
		} else {
			return null;
		}
	}

	/**
	 * 获取ttf属性集合
	 * 
	 * @return 属性集合(MAP)
	 */
	public Map<Integer, String> getFontProperties() {
		return fontProperties;
	}

	/**
	 * 执行解析 —— 毫秒级别
	 * 
	 * @param fileName
	 *            ttf文件名
	 * 
	 * @throws IOException
	 */
	public void parse(String fileName) throws IOException {
		fontProperties.clear();
		RandomAccessFile f = null;
		try {
			f = new RandomAccessFile(fileName, "r");
			parseInner(f);
		} finally {
			try {
				f.close();
			} catch (Exception e) {
				// ignore;
			}
		}
	}

	private void parseInner(RandomAccessFile randomAccessFile) throws IOException {
		int majorVersion = randomAccessFile.readShort();
		int minorVersion = randomAccessFile.readShort();
		int numOfTables = randomAccessFile.readShort();
		if (majorVersion != 1 || minorVersion != 0) {
			return;
		}
		// jump to TableDirectory struct
		randomAccessFile.seek(12);
		boolean found = false;
		byte[] buff = new byte[4];
		TableDirectory tableDirectory = new TableDirectory();
		for (int i = 0; i < numOfTables; i++) {
			randomAccessFile.read(buff);
			tableDirectory.name = new String(buff);
			tableDirectory.checkSum = randomAccessFile.readInt();
			tableDirectory.offset = randomAccessFile.readInt();
			tableDirectory.length = randomAccessFile.readInt();
			if ("name".equalsIgnoreCase(tableDirectory.name)) {
				found = true;
				break;
			} else if (tableDirectory.name == null || tableDirectory.name.length() == 0) {
				break;
			}
		}
		// not found table of name
		if (!found) {
			return;
		}
		randomAccessFile.seek(tableDirectory.offset);
		NameTableHeader nameTableHeader = new NameTableHeader();
		nameTableHeader.fSelector = randomAccessFile.readShort();
		nameTableHeader.nRCount = randomAccessFile.readShort();
		nameTableHeader.storageOffset = randomAccessFile.readShort();
		NameRecord nameRecord = new NameRecord();
		for (int i = 0; i < nameTableHeader.nRCount; i++) {
			nameRecord.platformID = randomAccessFile.readShort();
			nameRecord.encodingID = randomAccessFile.readShort();
			nameRecord.languageID = randomAccessFile.readShort();
			nameRecord.nameID = randomAccessFile.readShort();
			nameRecord.stringLength = randomAccessFile.readShort();
			nameRecord.stringOffset = randomAccessFile.readShort();
			long pos = randomAccessFile.getFilePointer();
			byte[] bf = new byte[nameRecord.stringLength];
			long vpos = tableDirectory.offset + nameRecord.stringOffset + nameTableHeader.storageOffset;
			randomAccessFile.seek(vpos);
			randomAccessFile.read(bf);
			String temp = new String(bf, "utf-16");//new String(bf, Charset.forName("utf-16"));
			fontProperties.put(nameRecord.nameID, temp);
			randomAccessFile.seek(pos);
		}
	}

	@Override
	public String toString() {
		return fontProperties.toString();
	}

	@SuppressWarnings("unused")
	private static class TableDirectory {
		String name; // table name
		int checkSum; // Check sum
		int offset; // Offset from beginning of file
		int length; // length of the table in bytes
	}

	@SuppressWarnings("unused")
	private static class NameTableHeader {
		int fSelector; // format selector. Always 0
		int nRCount; // Name Records count
		int storageOffset; // Offset for strings storage,
	}

	@SuppressWarnings("unused")
	private static class NameRecord {
		int platformID;
		int encodingID;
		int languageID;
		int nameID;
		int stringLength;
		int stringOffset; // from start of storage area
	}
}