cfffontsubset.java

iText是一个能够快速产生PDF文件的java类库。iText的java类对于那些要产生包含文本

			return 1131;
		else
			return 32768;
	}

	/**
	 *Function uses BuildNewIndex to create the new index of the subset charstrings
	 * @param FontIndex the font
	 * @throws IOException
	 */
	protected void BuildNewCharString(int FontIndex) throws IOException 
	{
		NewCharStringsIndex = BuildNewIndex(fonts[FontIndex].charstringsOffsets,GlyphsUsed);
	}
	
	/**
	 * Function builds the new local & global subsrs indices. IF CID then All of 
	 * the FD Array lsubrs will be subsetted. 
	 * @param Font the font
	 * @throws IOException
	 */
	protected void BuildNewLGSubrs(int Font)throws IOException
	{
		// If the font is CID then the lsubrs are divided into FontDicts.
		// for each FD array the lsubrs will be subsetted.
		if(fonts[Font].isCID)
		{
			// Init the hasmap-array and the arraylist-array to hold the subrs used
			// in each private dict.
			hSubrsUsed = new HashMap[fonts[Font].fdprivateOffsets.length];
			lSubrsUsed = new ArrayList[fonts[Font].fdprivateOffsets.length];
			// A [][] which will store the byte array for each new FD Array lsubs index
			NewLSubrsIndex = new byte[fonts[Font].fdprivateOffsets.length][];
			// An array to hold the offset for each Lsubr index 
			fonts[Font].PrivateSubrsOffset = new int[fonts[Font].fdprivateOffsets.length];
			// A [][] which will store the offset array for each lsubr index			
			fonts[Font].PrivateSubrsOffsetsArray = new int[fonts[Font].fdprivateOffsets.length][];
			
			// Put the FDarrayUsed into a list
			ArrayList FDInList = new ArrayList(FDArrayUsed.keySet());
			// For each FD array which is used subset the lsubr 
			for (int j=0;j<FDInList.size();j++)
			{
				// The FDArray index, Hash Map, Arrat List to work on
				int FD = ((Integer)FDInList.get(j)).intValue();
				hSubrsUsed[FD] = new HashMap();
				lSubrsUsed[FD] = new ArrayList();
				//Reads the private dicts looking for the subr operator and 
				// store both the offest for the index and its offset array
				BuildFDSubrsOffsets(Font,FD);
				// Verify that FDPrivate has a LSubrs index
				if(fonts[Font].PrivateSubrsOffset[FD]>=0)
				{
					//Scans the Charsting data storing the used Local and Global subroutines 
					// by the glyphs. Scans the Subrs recursivley. 
					BuildSubrUsed(Font,FD,fonts[Font].PrivateSubrsOffset[FD],fonts[Font].PrivateSubrsOffsetsArray[FD],hSubrsUsed[FD],lSubrsUsed[FD]);
					// Builds the New Local Subrs index
					NewLSubrsIndex[FD] = BuildNewIndex(fonts[Font].PrivateSubrsOffsetsArray[FD],hSubrsUsed[FD]);
				}
			}
		}
		// If the font is not CID && the Private Subr exists then subset:
		else if (fonts[Font].privateSubrs>=0)
		{
			// Build the subrs offsets;
			fonts[Font].SubrsOffsets = getIndex(fonts[Font].privateSubrs);
			//Scans the Charsting data storing the used Local and Global subroutines 
			// by the glyphs. Scans the Subrs recursivley.
			BuildSubrUsed(Font,-1,fonts[Font].privateSubrs,fonts[Font].SubrsOffsets,hSubrsUsedNonCID,lSubrsUsedNonCID);
		}
		// For all fonts susbset the Global Subroutines
		// Scan the Global Subr Hashmap recursivly on the Gsubrs
		BuildGSubrsUsed(Font);
		if (fonts[Font].privateSubrs>=0)
			// Builds the New Local Subrs index
			NewSubrsIndexNonCID = BuildNewIndex(fonts[Font].SubrsOffsets,hSubrsUsedNonCID);
		//Builds the New Global Subrs index
		NewGSubrsIndex = BuildNewIndex(gsubrOffsets,hGSubrsUsed);
	}

	/**
	 * The function finds for the FD array processed the local subr offset and its 
	 * offset array.  
	 * @param Font the font
	 * @param FD The FDARRAY processed
	 */
	protected void BuildFDSubrsOffsets(int Font,int FD)
	{
		// Initiate to -1 to indicate lsubr operator present
		fonts[Font].PrivateSubrsOffset[FD] = -1;
		// Goto begining of objects
        seek(fonts[Font].fdprivateOffsets[FD]);
        // While in the same object:
        while (getPosition() < fonts[Font].fdprivateOffsets[FD]+fonts[Font].fdprivateLengths[FD])
        {
        	getDictItem();
        	// If the dictItem is the "Subrs" then find and store offset, 
        	if (key=="Subrs")
        		fonts[Font].PrivateSubrsOffset[FD] = ((Integer)args[0]).intValue()+fonts[Font].fdprivateOffsets[FD];
        }
        //Read the lsub index if the lsubr was found
        if (fonts[Font].PrivateSubrsOffset[FD] >= 0)
        	fonts[Font].PrivateSubrsOffsetsArray[FD] = getIndex(fonts[Font].PrivateSubrsOffset[FD]); 
	}

	/**
	 * Function uses ReadAsubr on the glyph used to build the LSubr & Gsubr HashMap.
	 * The HashMap (of the lsub only) is then scaned recursivly for Lsubr & Gsubrs
	 * calls.  
	 * @param Font the font
	 * @param FD FD array processed. 0 indicates function was called by non CID font
	 * @param SubrOffset the offset to the subr index to calc the bias
	 * @param SubrsOffsets the offset array of the subr index
	 * @param hSubr HashMap of the subrs used
	 * @param lSubr ArrayList of the subrs used
	 */
	protected void BuildSubrUsed(int Font,int FD,int SubrOffset,int[] SubrsOffsets,HashMap hSubr,ArrayList lSubr)
	{

		// Calc the Bias for the subr index
		int LBias = CalcBias(SubrOffset,Font);
		
		// For each glyph used find its GID, start & end pos
		for (int i=0;i<glyphsInList.size();i++)
		{
			int glyph = ((Integer)glyphsInList.get(i)).intValue();
			int Start = fonts[Font].charstringsOffsets[glyph];
			int End = fonts[Font].charstringsOffsets[glyph+1];
			
			// IF CID:
			if (FD >= 0)
			{
				EmptyStack();
				NumOfHints=0;
				// Using FDSELECT find the FD Array the glyph belongs to.
				int GlyphFD = fonts[Font].FDSelect[glyph];
				// If the Glyph is part of the FD being processed 
				if (GlyphFD == FD)
					// Find the Subrs called by the glyph and insert to hash:
					ReadASubr(Start,End,GBias,LBias,hSubr,lSubr,SubrsOffsets);
			}
			else
				// If the font is not CID 
				//Find the Subrs called by the glyph and insert to hash:
				ReadASubr(Start,End,GBias,LBias,hSubr,lSubr,SubrsOffsets);
		}
		// For all Lsubrs used, check recusrivly for Lsubr & Gsubr used
		for (int i=0;i<lSubr.size();i++)
		{
			// Pop the subr value from the hash
			int Subr = ((Integer)lSubr.get(i)).intValue();
			// Ensure the Lsubr call is valid
			if (Subr < SubrsOffsets.length-1 && Subr>=0)
			{
				// Read and process the subr
				int Start = SubrsOffsets[Subr];
				int End = SubrsOffsets[Subr+1];
				ReadASubr(Start,End,GBias,LBias,hSubr,lSubr,SubrsOffsets);
			}
		}
	}
	
	/**
	 * Function scans the Glsubr used ArrayList to find recursive calls 
	 * to Gsubrs and adds to Hashmap & ArrayList
	 * @param Font the font
	 */
	protected void BuildGSubrsUsed(int Font)
	{
		int LBias = 0;
		int SizeOfNonCIDSubrsUsed = 0;
		if (fonts[Font].privateSubrs>=0)
		{
			LBias = CalcBias(fonts[Font].privateSubrs,Font);
			SizeOfNonCIDSubrsUsed = lSubrsUsedNonCID.size();
		}
		
		// For each global subr used 
		for (int i=0;i<lGSubrsUsed.size();i++)
		{
			//Pop the value + check valid 
			int Subr = ((Integer)lGSubrsUsed.get(i)).intValue();
			if (Subr < gsubrOffsets.length-1 && Subr>=0)
			{
				// Read the subr and process
				int Start = gsubrOffsets[Subr];
				int End = gsubrOffsets[Subr+1];
				
				if (fonts[Font].isCID)
					ReadASubr(Start,End,GBias,0,hGSubrsUsed,lGSubrsUsed,null);
				else
				{
					ReadASubr(Start,End,GBias,LBias,hSubrsUsedNonCID,lSubrsUsedNonCID,fonts[Font].SubrsOffsets);
					if (SizeOfNonCIDSubrsUsed < lSubrsUsedNonCID.size())
					{
						for (int j=SizeOfNonCIDSubrsUsed;j<lSubrsUsedNonCID.size();j++)
						{
							//Pop the value + check valid 
							int LSubr = ((Integer)lSubrsUsedNonCID.get(j)).intValue();
							if (LSubr < fonts[Font].SubrsOffsets.length-1 && LSubr>=0)
							{
								// Read the subr and process
								int LStart = fonts[Font].SubrsOffsets[LSubr];
								int LEnd = fonts[Font].SubrsOffsets[LSubr+1];
								ReadASubr(LStart,LEnd,GBias,LBias,hSubrsUsedNonCID,lSubrsUsedNonCID,fonts[Font].SubrsOffsets);
							}
						}
						SizeOfNonCIDSubrsUsed = lSubrsUsedNonCID.size();
					}
				}
			}
		}
	}

	/**
	 * The function reads a subrs (glyph info) between begin and end.
	 * Adds calls to a Lsubr to the hSubr and lSubrs.
	 * Adds calls to a Gsubr to the hGSubr and lGSubrs.
	 * @param begin the start point of the subr
	 * @param end the end point of the subr
	 * @param GBias the bias of the Global Subrs
	 * @param LBias the bias of the Local Subrs
	 * @param hSubr the HashMap for the lSubrs
	 * @param lSubr the ArrayList for the lSubrs
	 */
	protected void ReadASubr(int begin,int end,int GBias,int LBias,HashMap hSubr,ArrayList lSubr,int[] LSubrsOffsets)
	{
		// Clear the stack for the subrs
		EmptyStack();
		NumOfHints = 0;
		// Goto begining of the subr
        seek(begin);
        while (getPosition() < end)
        {
        	// Read the next command
        	ReadCommand();
        	int pos = getPosition();
        	Object TopElement=null;
        	if (arg_count > 0)
        		TopElement = args[arg_count-1];
        	int NumOfArgs = arg_count;
        	// Check the modification needed on the Argument Stack according to key;
        	HandelStack();
        	// a call to a Lsubr
        	if (key=="callsubr") 
        	{
        		// Verify that arguments are passed 
        		if (NumOfArgs > 0)
        		{
            		// Calc the index of the Subrs
            		int Subr = ((Integer)TopElement).intValue() + LBias;
            		// If the subr isn't in the HashMap -> Put in
        			if (!hSubr.containsKey(new Integer (Subr)))
            		{
            			hSubr.put(new Integer(Subr),null);
            			lSubr.add(new Integer(Subr));
            		}
        			CalcHints(LSubrsOffsets[Subr],LSubrsOffsets[Subr+1],LBias,GBias,LSubrsOffsets);
        			seek(pos);
        		}        		
        	}
        	// a call to a Gsubr
        	else if (key=="callgsubr")
        	{
        		// Verify that arguments are passed 
        		if (NumOfArgs > 0)
        		{
	        		// Calc the index of the Subrs
	        		int Subr = ((Integer)TopElement).intValue() + GBias;
	        		// If the subr isn't in the HashMap -> Put in
	        		if (!hGSubrsUsed.containsKey(new Integer (Subr)))
	        		{
	        			hGSubrsUsed.put(new Integer(Subr),null);
	        			lGSubrsUsed.add(new Integer(Subr));
	        		}
	        		CalcHints(gsubrOffsets[Subr],gsubrOffsets[Subr+1],LBias,GBias,LSubrsOffsets);
	        		seek(pos);
        		}
        	}
        	// A call to "stem"
        	else if (key == "hstem" || key == "vstem" || key == "hstemhm" || key == "vstemhm")
        		// Increment the NumOfHints by the number couples of of arguments
        		NumOfHints += NumOfArgs/2;
        	// A call to "mask"
        	else if (key == "hintmask" || key == "cntrmask")
        	{
        		// Compute the size of the mask
        		int SizeOfMask = NumOfHints/8;
        		if (NumOfHints%8 != 0 || SizeOfMask == 0)
        			SizeOfMask++;
        		// Continue the pointer in SizeOfMask steps
        		for (int i=0;i<SizeOfMask;i++)
        			getCard8();
        	}
        }
	}

	/**
	 * Function Checks how the current operator effects the run time stack after being run 
	 * An operator may increase or decrease the stack size
	 */
	protected void HandelStack()
	{
    	// Findout what the operator does to the stack
    	int StackHandel = StackOpp();
    	if (StackHandel < 2)
    	{
    		// The operators that enlarge the stack by one
    		if (StackHandel==1)
    			PushStack();
    		// The operators that pop the stack
    		else
    		{
    			// Abs value for the for loop
    			StackHandel *= -1;
    			for (int i=0;i<StackHandel;i++)
    				PopStack();
    		}
    		
    	}
    	// All other flush the stack
    	else
    		EmptyStack();		
	}
	
	/**
	 * Function checks the key and return the change to the stack after the operator
	 * @return The change in the stack. 2-> flush the stack
	 */
	protected int StackOpp()
	{
		if (key == "ifelse")
			return -3;
		if (key == "roll" || key == "put")
			return -2;
		if (key == "callsubr" || key == "callgsubr" || key == "add" || key == "sub" ||
			key == "div" || key == "mul" || key == "drop" || key == "and" || 
			key == "or" || key == "eq")
			return -1;
		if (key == "abs" || key == "neg" || key == "sqrt" || key == "exch" || 
			key == "index" || key == "get" || key == "not" || key == "return")
			return 0;
		if (key == "random" || key == "dup")
			return 1;
		return 2;
	}
	
	/**
	 * Empty the Type2 Stack
	 *
	 */
	protected void EmptyStack()
	{
		// Null the arguments
    	for (int i=0; i<arg_count; i++) args[i]=null;
        arg_count = 0;		
	}
	
	/**
	 * Pop one element from the stack 
	 *
	 */
	protected void PopStack()
	{
		if (arg_count>0)
		{
			args[arg_count-1]=null;
			arg_count--;
		}
	}
	
	/**
	 * Add an item to the stack
	 *
	 */
	protected void PushStack()
	{
		arg_count++;
	}
	
	/**
	 * The function reads the next command after the file pointer is set
	 */
	protected void ReadCommand()
	{
        key = null;
        boolean gotKey = false;
        // Until a key is found
        while (!gotKey) {
        	// Read the first Char
            char b0 = getCard8();
            // decode according to the type1/type2 format
            if (b0 == 28) // the two next bytes represent a short int;
            {
            	int first = getCard8();
            	int second = getCard8();
            	args[arg_count] = new Integer(first<<8 | second);
            	arg_count++;
            	continue;
            }
            if (b0 >= 32 && b0 <= 246) // The byte read is the byte;
            {
            	args[arg_count] = new Integer(b0 - 139);
            	arg_count++;
            	continue;
            }
            if (b0 >= 247 && b0 <= 250) // The byte read and the next byte constetute a short int