spring3.0学习笔记三---SpEL表达式2
例一：使用符号//evaluates to trueboolean trueValue=parser.parseExpression("2==2").getValue(Boolean.class);//evaluates to falseboolean falseValue=parser.parseExpression("2<-5.0").getValue(Boolean.class);//evaluates to trueboolean trueValue=parser.parseExpression("'black'<'block'").getValue(Boolean.class); //字符串的比较例二：判断是否是类中的一个实例//evaluates to falseboolean falseValue=parser.parseExpression("'xyz' instanceofT(int)").getValue(Boolean.class);例三：和正则表达式结合//evaluates to trueboolean trueValue = parser.parseExpression("'5.00'matches'^-?\\d+\\.\\d{2})?$'").getValue(Boolean.class);//evaluates to falseboolean falseValue = parser.parseExpression("'5.0067'matches'^-?\\d+(\\.\\d{2})?$'").getValue(Boolean.class);例四：逻辑运算符//--AND--//evaluates to falseboolean falseValue=parser.parseExpression("true and false").getValue(Boolean.class);//取后者//evaluates to trueString expression= "isMember('NikolaTesla') and isMember('MihajloPupin')";boolean trueValue=parser.parseExpression(expression).getValue(societyContext,Boolean.class);//--OR--//evaluates to trueboolean trueValue=parser.parseExpression("true or false").getValue(Boolean.class);//evaluates to trueString expression= "isMember('Nikola Tesla') or isMember('Albert Einstien')";boolean trueValue=parser.parseExpression(expression).getValue(societyContext,Boolean.class);//--NOT--//evaluates to falseboolean falseValue=parser.parseExpression(" !true").getValue(Boolean.class);//--AND and NOT--String expression= "isMember('NikolaTesla') and !isMember('MihajloPupin')";boolean falseValue=parser.parseExpression(expression).getValue(societyContext,Boolean.class);例五：算术运算符//Additionint two=parser.parseExpression("1+1").getValue(Integer.class); //2String testString=parser.parseExpression(" 'test'+'string' ").getValue(String.class); //'teststring'//Subtractionint four=parser.parseExpression("1-3").getValue(Integer.class); //4double d=parser.parseExpression("1000.00-1e4").getValue(Double.class); //-9000//Multiplicationint six=parser.parseExpression("-2*-3").getValue(Integer.class); //6double twentyFour=parser.parseExpression("2.0*3e0*4").getValue(Double.class); //24.0//Divisionint minusTwo=parser.parseExpression("6/-3").getValue(Integer.class); //-2double one=parser.parseExpression("8.0/4e0/2").getValue(Double.class); //1.0//Modulusint three=parser.parseExpression("7%4").getValue(Integer.class); //3int one=parser.parseExpression("8/5%2").getValue(Integer.class); //1//Operator precedenceint minusTwentyOne=parser.parseExpression("1+2-3*8").getValue(Integer.class); //-21?