001 package railo.runtime.type; 002 003 import railo.runtime.PageContext; 004 import railo.runtime.dump.DumpData; 005 import railo.runtime.dump.DumpProperties; 006 import railo.runtime.dump.DumpUtil; 007 import railo.runtime.dump.Dumpable; 008 import railo.runtime.exp.ExpressionException; 009 import railo.runtime.exp.PageException; 010 import railo.runtime.op.Castable; 011 import railo.runtime.type.dt.DateTime; 012 013 /** 014 * Custom Null Type 015 */ 016 public final class Null implements Castable,Dumpable { 017 public static final Null NULL=new Null(); 018 private Null() {} 019 020 @Override 021 public String castToString() throws ExpressionException { 022 return ""; 023 } 024 025 @Override 026 public String castToString(String defaultValue) { 027 return ""; 028 } 029 030 @Override 031 public boolean castToBooleanValue() throws ExpressionException { 032 throw new ExpressionException("can't convert null to a boolean"); 033 } 034 035 @Override 036 public Boolean castToBoolean(Boolean defaultValue) { 037 return defaultValue; 038 } 039 040 @Override 041 public double castToDoubleValue() throws ExpressionException { 042 throw new ExpressionException("can't convert null to a numberic value"); 043 } 044 045 @Override 046 public double castToDoubleValue(double defaultValue) { 047 return defaultValue; 048 } 049 050 @Override 051 public DateTime castToDateTime() throws ExpressionException { 052 throw new ExpressionException("can't convert null to a date object"); 053 } 054 055 @Override 056 public DateTime castToDateTime(DateTime defaultValue) { 057 return defaultValue; 058 } 059 060 @Override 061 public DumpData toDumpData(PageContext pageContext, int maxlevel, DumpProperties dp) { 062 return DumpUtil.toDumpData(null,pageContext,maxlevel,dp); 063 } 064 @Override 065 public String toString() { 066 return null; 067 } 068 public int compareTo(String str) throws PageException { 069 return "".compareTo(str); 070 //throw new ExpressionException("can't compare null with a string value"); 071 } 072 public int compareTo(boolean b) throws PageException { 073 throw new ExpressionException("can't compare null with a boolean value"); 074 } 075 public int compareTo(double d) throws PageException { 076 throw new ExpressionException("can't compare null with a numeric value"); 077 } 078 public int compareTo(DateTime dt) throws PageException { 079 throw new ExpressionException("can't compare null with a date object"); 080 } 081 }