I downed a pdf from http://www.deelin.com/downloads/books/java_concurrency_in_practice.pdf
 When I tried to convert it to MOBI using calibre, it had the following error.
I was told by the calibre team that this is a poppler issue, so here I am.
 
calibre, version 0.8.31
 ERROR: Conversion Error: <b>Failed</b>: Convert book 1 of 1 (Java Concurrency In Practice)
 
Convert book 1 of 1 (Java Concurrency In Practice)
 Resolved conversion options
 calibre version: 0.8.31
 {'asciiize': False,
  'author_sort': None,
  'authors': None,
  'base_font_size': 0.0,
  'book_producer': None,
  'change_justification': u'original',
  'chapter': u"//*[((name()='h1' or name()='h2') and re:test(., 'chapter|book|section|part|prologue|epilogue\\s+', 'i')) or @class = 'chapter']",
  'chapter_mark': u'pagebreak',
  'comments': None,
  'cover': 'c:\\users\\ming\\appdata\\local\\temp\\calibre_0.8.31_tmp_skdlbl\\gxxwic.jpeg',
  'debug_pipeline': None,
  'dehyphenate': True,
  'delete_blank_paragraphs': True,
  'disable_font_rescaling': False,
  'dont_compress': False,
  'duplicate_links_in_toc': False,
  'enable_heuristics': False,
  'extra_css': None,
  'extract_to': None,
  'filter_css': u'',
  'fix_indents': True,
  'font_size_mapping': None,
  'format_scene_breaks': True,
  'html_unwrap_factor': 0.4,
  'input_encoding': None,
  'input_profile': <calibre.customize.profiles.InputProfile object at 0x058448D0>,
  'insert_blank_line': False,
  'insert_blank_line_size': 0.5,
  'insert_metadata': False,
  'isbn': None,
  'italicize_common_cases': True,
  'keep_ligatures': False,
  'language': None,
  'level1_toc': None,
  'level2_toc': None,
  'level3_toc': None,
  'line_height': 0.0,
  'linearize_tables': False,
  'margin_bottom': 5.0,
  'margin_left': 5.0,
  'margin_right': 5.0,
  'margin_top': 5.0,
  'markup_chapter_headings': True,
  'max_toc_links': 50,
  'minimum_line_height': 120.0,
  'mobi_ignore_margins': False,
  'mobi_toc_at_start': False,
  'new_pdf_engine': False,
  'no_chapters_in_toc': False,
  'no_images': False,
  'no_inline_navbars': True,
  'no_inline_toc': False,
  'output_profile': <calibre.customize.profiles.KindleDXOutput object at 0x05844C10>,
  'page_breaks_before': u"//*[name()='h1' or name()='h2']",
  'personal_doc': u'[PDOC]',
  'prefer_author_sort': False,
  'prefer_metadata_cover': False,
  'pretty_print': False,
  'pubdate': None,
  'publisher': None,
  'rating': None,
  'read_metadata_from_opf': 'c:\\users\\ming\\appdata\\local\\temp\\calibre_0.8.31_tmp_skdlbl\\1bocnx.opf',
  'remove_fake_margins': True,
  'remove_first_image': False,
  'remove_paragraph_spacing': False,
  'remove_paragraph_spacing_indent_size': 1.5,
  'renumber_headings': True,
  'replace_scene_breaks': u'',
  'rescale_images': False,
  'series': None,
  'series_index': None,
  'share_not_sync': False,
  'smarten_punctuation': False,
  'sr1_replace': None,
  'sr1_search': None,
  'sr2_replace': None,
  'sr2_search': None,
  'sr3_replace': None,
  'sr3_search': None,
  'tags': None,
  'timestamp': None,
  'title': None,
  'title_sort': None,
  'toc_filter': None,
  'toc_threshold': 6,
  'toc_title': None,
  'unsmarten_punctuation': False,
  'unwrap_factor': 0.45,
  'unwrap_lines': True,
  'use_auto_toc': False,
  'verbose': 2}
 InputFormatPlugin: PDF Input running
 on c:\users\ming\appdata\local\temp\calibre_0.8.31_tmp_skdlbl\xpeorn.pdf
 Converting file to html...
 Python function terminated unexpectedly
 
This application has requested the Runtime to terminate it in an unusual way.
 Please contact the application's support team for more information.
  (Error Code: 1)
 Traceback (most recent call last):
   File "site.py", line 132, in main
   File "site.py", line 109, in run_entry_point
   File "site-packages\calibre\utils\ipc\worker.py", line 187, in main
   File "site-packages\calibre\gui2\convert\gui_conversion.py", line 31, in gui_convert_override
   File "site-packages\calibre\gui2\convert\gui_conversion.py", line 25, in gui_convert
   File "site-packages\calibre\ebooks\conversion\plumber.py", line 959, in run
   File "site-packages\calibre\customize\conversion.py", line 204, in __call__
   File "site-packages\calibre\ebooks\pdf\input.py", line 51, in convert
   File "site-packages\calibre\ebooks\pdf\pdftohtml.py", line 74, in pdftohtml
 calibre.ebooks.ConversionError:
 This application has requested the Runtime to terminate it in an unusual way.
 Please contact the application's support team for more information.