Java methods for generating tables in PDF _java

1. Target

Generate a table with variable headers in the PDF and populate it with data. Dynamically generating tables are achieved by dynamically fetching the entity class (I here is user) by using a generic dynamic generation header to obtain the data in a dynamic way.

Generate one Folder store per day (name of the folder is the date of year), such as: 20151110

The generated file may be at the millisecond level, so the file's naming rule is "to the time stamp-uuid in milliseconds", such as: 20151110100245690-ece540e5-7737-4ab7-b2d6-87bc23917c8c.pdf

Dynamically obtain the directory of the file store by reading the properties file.

2, the required jar

Here through the Itex Plug-ins for PDF generation, the need for the jar includes the following several

3, coding implementation

1), Entity class

Package com.zcr.until;
 public class User {private String name;
 private int age;
 private float height;
 Private String adress;
 Private String sex;
 
 Private String JJ;
 Public String GETJJ () {return JJ;
 public void Setjj (String jj) {this.jj = JJ; Public user () {} public user (String name,int age,float height,string adress,string sex,string JJ) {This.nam
  e = name;
  This.age = age;
  This.height = height;
  this.adress = adress;
  This.sex = sex;
 THIS.JJ = JJ;
 Public String getadress () {return adress;
 } public void Setadress (String adress) {this.adress = adress;
 Public String Getsex () {return sex;
 } public void Setsex (String sex) {this.sex = sex;
 Public String GetName () {return name;
 public void SetName (String name) {this.name = name;
 public int getage () {return age;
 public void Setage (int age) {this.age = age;
 public float getheight () {return height; } public void SetHeight (Float height) {this.height = height;
 }
 
}

2), properties file

Pdfpath=e\:/appdatapdf
3, read the properties file, get the PDF storage path

Package com.zcr.until;
Import Java.io.BufferedInputStream;
Import Java.io.File;
Import Java.io.FileInputStream;
Import java.io.IOException;
Import Java.io.InputStream;

Import java.util.Properties; public class Getfileplace {/** * Read the file, get the root directory saved by Excel * @return Excel saved root/public String GetFilePath () {St Ring dir = System.getproperty ("User.dir"); Get Tomcat's working path//Get to the Filedir.properties file path where the file storage location is stored--->java project's file path String realdir = dir + File.sepa
  
　　　　 Rator + "src" + file.separator + "Meta-inf" + file.separator + "filedir.properties"; WEB Project Storage path/*string Realdir = dir.substring (0, Dir.length ()-4) + File.separator + "WebApps" + file.separator + "ge Nerateexcels "+ file.separator +" classes "+ File.separator +" Meta-inf "+ file.separator +" config "+ File.separat
 or + "filedir.properties";
 * * return realdir; /** * Gets the value of key in FilePath path "Properities file", * @param filePath properities file path "contains properities file" * @param key to find
Key value  * @return key corresponding to value/public String Getvaluebykey (string filePath, String key) {Properties pps = new Prope
   Rties (); 
    try {inputstream in = new Bufferedinputstream (new FileInputStream (FilePath));
    Pps.load (in);
    String value = Pps.getproperty (key);
    In.close ();
    
   return value;
    }catch (IOException e) {e.printstacktrace ();
   return null; }/** * Query properities file can be the corresponding storage location * @param key Query primary key * @return key corresponding to the storage address * * Public String GETFILEDIRFROMPR
 Operties (String key) {return Getvaluebykey (GetFilePath (), key);

 }

}

4, get the file path that exists on the day, do not exist to generate a new folder

Package com.zcr.service;

Import Java.io.File;
Import Java.text.SimpleDateFormat;
Import Java.util.Calendar;

public class Generatefold
{
 /**
  * Query which path the currently generated Excel needs to exist, if it exists, store it in the appropriate location, or generate a change directory, generate a folder every day, and the folder's naming rules are Time Stamp
  * @param foldname Build Excel save path
  * @return   now Excel needs to save the path/public
 String Getfold ( String foldname)
 {
  SimpleDateFormat format = new SimpleDateFormat ("YyyyMMdd");
  
  String todaystr = Format.format (Calendar.getinstance (). GetTime ());
  
  String Foldpath = foldname + File.separator + todaystr; 
  
  File File = new file (Foldpath);
  
  if (!file.exists () &&!file.isdirectory ())
  {
   System.out.println ("does not exist");
   File.mkdirs ();
  }
  else
  {
   System.out.println ("exist");
  }
  Return Foldpath
 }

}

5), the name of the generated file

Package com.zcr.until;

Import Java.io.File;
Import Java.text.SimpleDateFormat;
Import Java.util.Calendar;
Import Java.util.UUID;

/**
 * Generate file name
 * @author ZCR
 * */public
class Generatefilename
{
 /**
  * The name of the file is generated from the file category, and the naming rule for the file is: File directory/build time-uuid (globally unique encoding). File category *
  @param filedir file storage path
  * @param fileType file category
  *     the name of the @return file
 //Public String generatefilename (string filedir,string fileType)
 {
  string Savefilename = "";
  SimpleDateFormat format = new SimpleDateFormat ("Yyyymmddhhmmssss");
  Savefilename + + Format.format (calendar.getinstance (). GetTime ());
  
  UUID uuid = Uuid.randomuuid (); The world's only code Savefilename + +
  
  + uuid.tostring ();
  Savefilename + = "." + FileType;
  
  Savefilename = filedir + File.separator + savefilename;
  
  Return Savefilename
 }
}

6), generate PDF

Package com.zcr.service;
Import Java.io.File;
Import Java.io.FileOutputStream;
Import java.io.IOException;
Import java.lang.reflect.InvocationTargetException;
Import Java.lang.reflect.Method;
Import java.util.ArrayList;

Import java.util.List;
Import com.lowagie.text.Document;
Import com.lowagie.text.DocumentException;
Import com.lowagie.text.Element;
Import Com.lowagie.text.Font;
Import com.lowagie.text.PageSize;
Import Com.lowagie.text.Phrase;
Import Com.lowagie.text.pdf.BaseFont;
Import Com.lowagie.text.pdf.PdfPCell;
Import com.lowagie.text.pdf.PdfPTable;
Import Com.lowagie.text.pdf.PdfWriter;
Import Com.zcr.until.GenerateFileName;
Import Com.zcr.until.GetFilePlace;

Import Com.zcr.until.User; /** * Generates PDF * @author ZCR * * */public class CreatePDF {Document document = new document ();//Create a Document object Priva
 Te static font headfont;//set font size private static font keyfont;//set font size private static font textfont;//set Font size static
  {///Chinese format basefont Bfchinese; try {//Set Chinese display Bfchinese = Basefont.createfont ("Stsong-light", "unigb-ucs2-h", basefont.not_embedded); Headfont = new Font (Bfchinese, font.bold);/set Font size Keyfont = new Font (Bfchinese, 8, font.bold);/Set Font size TEXTFO
  NT = new Font (Bfchinese, 8, font.normal);//Set Font size} catch (Exception e) {e.printstacktrace (); }/** * Wencheng files * @param file file to be generated * * * Public createpdf (file file) {document.setpagesize (PAGESIZE.A4);//Set
   Page size try {pdfwriter.getinstance (document, new FileOutputStream (file));
  Document.open ();
  catch (Exception e) {e.printstacktrace ();
  } public CreatePDF () {} public void Initfile (file file) {document.setpagesize (PAGESIZE.A4);//Set Page size
   try {pdfwriter.getinstance (document, new FileOutputStream (file));
  Document.open ();
  catch (Exception e) {e.printstacktrace ();
 
 an int maxwidth = 520; /** * Add a content to the table * @param value * @param font font * @param align Alignment * @Return Added text box */public Pdfpcell Createcell (String value, font font, int align) {pdfpcell cell = new Pdfpcell ();
  Cell.setverticalalignment (Element.align_middle);
  Cell.sethorizontalalignment (align);
  Cell.setphrase (New Phrase (value, font));
 return cell; /** * Add a content to the table * @param value * @param font font * @return added textbox * * Public Pdfpcell Createcell (St
  Ring value, font font) {Pdfpcell cell = new Pdfpcell ();
  Cell.setverticalalignment (Element.align_middle);
  Cell.sethorizontalalignment (Element.align_center);
  Cell.setphrase (New Phrase (value, font));
 return cell; /** * Add a content to the table * @param value * @param font font * @param align alignment * @param colspan how many columns * @retu RN Added text box */public Pdfpcell Createcell (String value, font font, int align, int colspan) {Pdfpcell cell = new Pd
  Fpcell ();
  Cell.setverticalalignment (Element.align_middle);
  Cell.sethorizontalalignment (align);
  Cell.setcolspan (colspan); Cell.setphrASE (new Phrase (value, font));
 return cell; /** * Add a content to the table * @param value * @param font font * @param align alignment * @param colspan how many columns * @par Am Boderflag a text box with a border * @return added */public Pdfpcell Createcell (String value, font font, int align, int colspa
  N, Boolean boderflag) {Pdfpcell cell = new Pdfpcell ();
  Cell.setverticalalignment (Element.align_middle);
  Cell.sethorizontalalignment (align);
  Cell.setcolspan (colspan);
  Cell.setphrase (New Phrase (value, font));
  Cell.setpadding (3.0f);
   if (!boderflag) {cell.setborder (0);
   Cell.setpaddingtop (15.0f);
  Cell.setpaddingbottom (8.0f);
 } return cell;
 /** * Create a Table object * @param the number of columns in colnumber table * @return generated Table object/public pdfptable createtable (int colnumber)
  {pdfptable table = new pdfptable (colnumber);
   try {table.settotalwidth (maxwidth);
   Table.setlockedwidth (TRUE);
   Table.sethorizontalalignment (Element.align_center); Table.getdefaultcell (). SetBorder (1);
  catch (Exception e) {e.printstacktrace ();
 return table;
  Public pdfptable createtable (float[] widths) {pdfptable table = new pdfptable (widths);
   try {table.settotalwidth (maxwidth);
   Table.setlockedwidth (TRUE);
   Table.sethorizontalalignment (Element.align_center);
  Table.getdefaultcell (). SetBorder (1);
  catch (Exception e) {e.printstacktrace ();
 return table;
  Public pdfptable createblanktable () {pdfptable table = new pdfptable (1);
  Table.getdefaultcell (). SetBorder (0);
  Table.addcell (Createcell ("", Keyfont));
  Table.setspacingafter (20.0f);
  Table.setspacingbefore (20.0f);
 return table; } public <T> void Generatepdf (String [] head,list<t> list,int colnum) {Class ClassType = list.get (0). GE
  
  Tclass ();

  Create a table with only 5 columns pdfptable table = createtable (colnum);
  
  Add notes, left, do not display borders Table.addcell (Createcell ("app info list:", Keyfont, Element.align_left, Colnum,false)); Sets the table header for (int i = 0; i < ColnUm;
  i++) {Table.addcell (Createcell (head[i), Keyfont, Element.align_center));
   } if (null!= list && list.size () > 0) {int size = List.size ();
    for (int i = 0; i < size; i++) {T t = list.get (i); 
     
     for (int j = 0; J < Colnum J + +) {//Get the first letter String Firstletter = head[j].substring (0,1). toUpperCase ();
     
     Gets the Get method, Getname,getage etc. String getmethodname = "getting" + Firstletter + head[j].substring (1);
     Method method;
      try {//The corresponding Get method is obtained by reflection, which is used to obtain the corresponding property value methods = Classtype.getmethod (Getmethodname, New class[]{});
        try {System.out.print (getmethodname + ":" + method.invoke (t, new class[]{}) + ",");
      Add Data Table.addcell (Createcell (Method.invoke (t, new class[]{}). toString (), Textfont));
      catch (IllegalArgumentException e) {e.printstacktrace ();
      catch (Illegalaccessexception e) {e.printstacktrace ();
}      catch (InvocationTargetException e) {e.printstacktrace ();
     } catch (SecurityException e) {e.printstacktrace ();
     catch (Nosuchmethodexception e) {e.printstacktrace ();
   } System.out.println ("");
  try {//Add a table to the document Document.add (table);
  catch (Documentexception e) {e.printstacktrace ();
 }//Close stream document.close (); 
 /** * Provides an externally invoked interface to generate a PDF with head header, list as data @param head//Data header * @param list//data * @return//excel Path
  Public <T> string Generatepdfs (string [] head,list<t> List) {final String FilePath = "Pdfpath";
 
  String savefilepathandname = "";
  
  Gets the stored root string savepath = new Getfileplace (). Getfiledirfromproperties (FilePath);
  
  Gets the path stored for the day, does not exist, generates the day's folder String Realsavepath = new Generatefold (). Getfold (Savepath);
  
  Savefilepathandname = new Generatefilename (). Generatefilename (Realsavepath, "pdf"); File file= new File (savefilepathandname);
  try {file.createnewfile ();
  catch (IOException E1) {//TODO auto-generated catch block E1.printstacktrace ();
  } initfile (file); try {file.createnewfile ();//Generate a PDF file} catch (IOException e) {//TODO auto-generated catch block e.pr
  Intstacktrace ();
  
  New CreatePDF (file). generatepdf (Head,list,head.length);
 return savefilepathandname;

 }

}

7), evaluation function

 public static void Main (string[] args) 
 {
  System.out.println ("Begin");
  
  String [] head = {' name ', ' sex ', ' adress ', ' height ', ' age ', ' JJ '};
  
  list<user> list = new arraylist<user> ();
  User User1 = new User ("Zhangsan", 1,1.1f, "Beijing", "male", "AA");
  User User2 = New User ("Lisi", 22222,3.2f, "Shanghai", "female", "BB");
  
  List.add (user1);
  List.add (user2);
  
  
  String FilePath = new CreatePDF (). Generatepdfs (head,list);
  System.out.println (FilePath);
  System.out.println ("End");
 }

8), test results

9), the contents of the document are as follows

Java how to generate a table in the PDF, I believe that through this simple example demo with a general understanding, we can go to experiment to see if it will achieve the desired results.