Package com.itextpdf.text.pdf

Class MemoryLimitsAwareHandler

  • public class MemoryLimitsAwareHandler
extends java.lang.Object
    A MemoryLimitsAwareHandler handles memory allocation and prevents decompressed pdf streams from occupation of more space than allowed.

    • Field Detail

      • SINGLE_SCALE_COEFFICIENT

        private static final int SINGLE_SCALE_COEFFICIENT
        See Also:
        Constant Field Values

      • SINGLE_DECOMPRESSED_PDF_STREAM_MIN_SIZE

        private static final int SINGLE_DECOMPRESSED_PDF_STREAM_MIN_SIZE
        See Also:
        Constant Field Values

      • SUM_OF_DECOMPRESSED_PDF_STREAMW_MIN_SIZE

        private static final long SUM_OF_DECOMPRESSED_PDF_STREAMW_MIN_SIZE
        See Also:
        Constant Field Values

      • maxSizeOfSingleDecompressedPdfStream

        private int maxSizeOfSingleDecompressedPdfStream

      • maxSizeOfDecompressedPdfStreamsSum

        private long maxSizeOfDecompressedPdfStreamsSum

      • allMemoryUsedForDecompression

        private long allMemoryUsedForDecompression

      • memoryUsedForCurrentPdfStreamDecompression

        private long memoryUsedForCurrentPdfStreamDecompression

      • considerCurrentPdfStream

        boolean considerCurrentPdfStream

    • Constructor Detail

      • MemoryLimitsAwareHandler

        public MemoryLimitsAwareHandler()
        Creates a MemoryLimitsAwareHandler which will be used to handle decompression of pdf streams. The max allowed memory limits will be generated by default.

      • MemoryLimitsAwareHandler

        public MemoryLimitsAwareHandler​(long documentSize)
        Creates a MemoryLimitsAwareHandler which will be used to handle decompression of pdf streams. The max allowed memory limits will be generated by default, based on the size of the document.
        Parameters:
        documentSize - the size of the document, which is going to be handled by iText.

    • Method Detail

      • getMaxSizeOfSingleDecompressedPdfStream

        public int getMaxSizeOfSingleDecompressedPdfStream()
        Gets the maximum allowed size which can be occupied by a single decompressed pdf stream.
        Returns:
        the maximum allowed size which can be occupied by a single decompressed pdf stream.

      • setMaxSizeOfSingleDecompressedPdfStream

        public MemoryLimitsAwareHandler setMaxSizeOfSingleDecompressedPdfStream​(int maxSizeOfSingleDecompressedPdfStream)
        Sets the maximum allowed size which can be occupied by a single decompressed pdf stream. This value correlates with maximum heap size. This value should not exceed limit of the heap size. iText will throw an exception if during decompression a pdf stream with two or more filters of identical type occupies more memory than allowed.
        Parameters:
        maxSizeOfSingleDecompressedPdfStream - the maximum allowed size which can be occupied by a single decompressed pdf stream.
        Returns:
        this MemoryLimitsAwareHandler instance.

      • getMaxSizeOfDecompressedPdfStreamsSum

        public long getMaxSizeOfDecompressedPdfStreamsSum()
        Gets the maximum allowed size which can be occupied by all decompressed pdf streams.
        Returns:
        the maximum allowed size value which streams may occupy

      • setMaxSizeOfDecompressedPdfStreamsSum

        public MemoryLimitsAwareHandler setMaxSizeOfDecompressedPdfStreamsSum​(long maxSizeOfDecompressedPdfStreamsSum)
        Sets the maximum allowed size which can be occupied by all decompressed pdf streams. This value can be limited by the maximum expected PDF file size when it's completely decompressed. Setting this value correlates with the maximum processing time spent on document reading iText will throw an exception if during decompression pdf streams with two or more filters of identical type occupy more memory than allowed.
        Parameters:
        maxSizeOfDecompressedPdfStreamsSum - he maximum allowed size which can be occupied by all decompressed pdf streams.
        Returns:
        this MemoryLimitsAwareHandler instance.

      • considerBytesOccupiedByDecompressedPdfStream

        MemoryLimitsAwareHandler considerBytesOccupiedByDecompressedPdfStream​(long numOfOccupiedBytes)
        Considers the number of bytes which are occupied by the decompressed pdf stream. If memory limits have not been faced, throws an exception.
        Parameters:
        numOfOccupiedBytes - the number of bytes which are occupied by the decompressed pdf stream.
        Returns:
        this MemoryLimitsAwareHandler instance.

      • endDecompressedPdfStreamProcessing

        MemoryLimitsAwareHandler endDecompressedPdfStreamProcessing()
        Ends handling of current pdf stream decompression. If memory limits have not been faced, throws an exception.
        Returns:
        this MemoryLimitsAwareHandler instance.

      • getAllMemoryUsedForDecompression

        long getAllMemoryUsedForDecompression()

      • calculateDefaultParameter

        private static long calculateDefaultParameter​(long documentSize,
                                              int scale,
                                              long min)

      • ensureCurrentStreamIsReset

        private void ensureCurrentStreamIsReset()