prod/net/jaekl/cfb/db/Column.java

   1 package net.jaekl.cfb.db;
   2
   3 import java.sql.PreparedStatement;
   4 import java.sql.SQLException;
   5 import java.util.Date;
   6
   7 import net.jaekl.cfb.util.Util;
   8
   9 // Copyright (C) 2015 Christian Jaekl
  10
  11 public class Column {
  12         public enum Type {
  13                 CHAR, INTEGER, TIMESTAMPTZ, VARCHAR
  14         };
  15         public enum Null {
  16                 NOT_NULL, NULL
  17         }
  18
  19         String m_name;
  20         Type m_type;
  21         int m_width;
  22         Null m_null;
  23
  24         public Column(String name, Type type, int width, Null canBeNull)
  25         {
  26                 m_name = name;
  27                 m_type = type;
  28                 m_width = width;
  29                 m_null = canBeNull;
  30         }
  31
  32         public String getName() { return m_name; }
  33         public Type getType() { return m_type; }
  34         public int getWidth() { return m_width; }
  35         public Null getNull() { return m_null; }
  36
  37         // Create a column based on an array of Objects
  38         // Input format:  { name, type, width, can_be_null }
  39         public static Column construct(Object[] spec) {
  40                 assert(null != spec);
  41                 assert(4 == spec.length);
  42                 assert(spec[0] instanceof String);
  43                 assert(spec[1] instanceof Type);
  44                 assert(spec[2] instanceof Number);
  45                 assert(spec[3] instanceof Null);
  46
  47                 String name = (String)(spec[0]);
  48                 Type type = (Type)(spec[1]);
  49                 Number width = (Number)(spec[2]);
  50                 Null canBeNull = (Null)(spec[3]);
  51
  52                 return new Column(name, type, width.intValue(), canBeNull);
  53         }
  54
  55         // Wrapper around PreparedStatement.setObject().
  56         // Note that indices start at 1, not at zero.
  57         public void setObject(PreparedStatement ps, int idx, Object obj) throws SQLException
  58         {
  59                 if (this.getType().equals(Type.TIMESTAMPTZ)) {
  60                         // Special case:  because there's no good way to read a TIMESTAMPTZ from
  61                         // the database using JDBC, we store it as an integer (milliseconds since
  62                         // the epoch, 01.01.1970 00:00:00.000 UTC).
  63                         Date date = (Date)obj;
  64                         ps.setLong(idx, date.getTime());
  65                 }
  66                 else {
  67                         ps.setObject(idx, obj);
  68                 }
  69         }
  70
  71         @Override
  72         public boolean equals(Object obj)
  73         {
  74                 if (null == obj) {
  75                         return false;
  76                 }
  77                 if (! (obj instanceof Column)) {
  78                         return false;
  79                 }
  80                 Column other = (Column)obj;
  81
  82                 if (! Util.objsAreEqual(this.getName(), other.getName())) {
  83                         return false;
  84                 }
  85                 if (! Util.objsAreEqual(this.getType(), other.getType())) {
  86                         return false;
  87                 }
  88                 if (this.getWidth() != other.getWidth()) {
  89                         return false;
  90                 }
  91                 if (! Util.objsAreEqual(this.getNull(), other.getNull())) {
  92                         return false;
  93                 }
  94
  95                 return true;
  96         }
  97
  98         @Override
  99         public int hashCode() {
 100                 int code = Util.objHashCode(getName())
 101                                  ^ Util.objHashCode(getType())
 102                                  ^ getWidth()
 103                                  ^ Util.objHashCode(getNull());
 104                 return code;
 105         }
 106 }