Package net.sf.jasperreports.engine.util

Class JRTypeSniffer

java.lang.Object
net.sf.jasperreports.engine.util.JRTypeSniffer
public final class JRTypeSniffer extends Object
Author:
George Stojanoff (gstojanoff@jaspersoft.com), Flavius Sana (flavius_sana@users.sourceforge.net)

  • Method Summary

    Modifier and Type
    Method
    Description
    static ImageTypeEnum
    getImageTypeValue(byte[] data)
     
    static boolean
    isGIF(byte[] data)
    Sniffs an incoming byte array to see if the first 3 characters are GIF.
    static boolean
    isJPEG(byte[] data)
    Sniffs an incoming byte array to see if the starting value is 0xffd8 which is the "header" for JPEG data Note: This method only really needs the first 2 bytes.
    static boolean
    isPNG(byte[] data)
    Sniffs an incoming byte array to see if the first eight bytes are the following (decimal) values: 137 80 78 71 13 10 26 10 which is the "signature" for PNG data See http://www.w3.org/TR/PNG/#5PNG-file-signature for more details.
    static boolean
    isTIFF(byte[] data)
    Sniffs an incoming byte array to see if the starting value is 0x4949 (little endian) or 0x4D4D (big endian) which is the "header" for TIFF data The TIFF standards supports both endians.
    static boolean
    isWEBP(byte[] data)
    Sniffs an incoming byte array to see if the starting values are matching the WEBP magic number.

    Methods inherited from class java.lang.Object

    clone, equals, finalize, getClass, hashCode, notify, notifyAll, toString, wait, wait, wait

  • Method Details

    • isGIF

      public static boolean isGIF(byte[] data)
      Sniffs an incoming byte array to see if the first 3 characters are GIF. This is also known as the GIF signature. See http://www.dcs.ed.ac.uk/home/mxr/gfx/2d/GIF87a.txt for more details Note: Perhaps we should be checking for the more restive string GIF87a but I am not sure if older GIF images are sill out there in use on the web. Note: This method only really needs the first 3 bytes.

    • isJPEG

      public static boolean isJPEG(byte[] data)
      Sniffs an incoming byte array to see if the starting value is 0xffd8 which is the "header" for JPEG data Note: This method only really needs the first 2 bytes.

    • isPNG

      public static boolean isPNG(byte[] data)
      Sniffs an incoming byte array to see if the first eight bytes are the following (decimal) values: 137 80 78 71 13 10 26 10 which is the "signature" for PNG data See http://www.w3.org/TR/PNG/#5PNG-file-signature for more details. Note: This method only really needs the first 8 bytes.

    • isTIFF

      public static boolean isTIFF(byte[] data)
      Sniffs an incoming byte array to see if the starting value is 0x4949 (little endian) or 0x4D4D (big endian) which is the "header" for TIFF data The TIFF standards supports both endians. See http://palimpsest.stanford.edu/bytopic/imaging/std/tiff5.html for more details. Note: This method only really needs the first 2 bytes.

    • isWEBP

      public static boolean isWEBP(byte[] data)
      Sniffs an incoming byte array to see if the starting values are matching the WEBP magic number. See https://en.wikipedia.org/wiki/WebP for more details. Note: This method only really needs the first 15 bytes.

    • getImageTypeValue

      public static ImageTypeEnum getImageTypeValue(byte[] data)