[OmniFaces utilities] The
concat() concatenate the string representation of the given objects.Function:
In order
to highlight the OmniFaces of:concat() function let's suppose that we have
the following two objects (Foo and Buzz):
public class
Foo implements Serializable {
private String foofat;
private String fooweight;
public Foo(String foofat, String fooweight) {
this.foofat = foofat;
this.fooweight = fooweight;
}
public String getFoofat() {
return foofat;
}
public void setFoofat(String foofat) {
this.foofat = foofat;
}
public String getFooweight() {
return fooweight;
}
public void setFooweight(String fooweight) {
this.fooweight = fooweight;
}
@Override
public String toString() {
return "Foo is " + foofat + ",
and his weight is " + fooweight + "! ";
}
}
public class
Buzz implements Serializable {
private String buzzfat;
private String buzzweight;
public Buzz(String buzzfat, String buzzweight)
{
this.buzzfat = buzzfat;
this.buzzweight = buzzweight;
}
public String getBuzzfat() {
return
buzzfat;
}
public void setBuzzfat(String buzzfat) {
this.buzzfat
= buzzfat;
}
public String getBuzzweight() {
return buzzweight;
}
public void setBuzzweight(String buzzweight) {
this.buzzweight
= buzzweight;
}
@Override
public String toString() {
return
"Buzz is " + buzzfat + ", and his weight is " + buzzweight+
"! ";
}
}
Now, let's
test the EL 2.2 concat() function, += EL 3.0
concatenation operator and the OmniFaces of:concat() function
for concatenating Foo and Buzz objects string representations:
<c:set
var="foobuzz"
value="#{(testBean.fooman.toString()).concat(testBean.buzzman.toString())}"/>
<c:set
var="foobuzz" value="#{testBean.fooman +=
testBean.buzzman}"/>
<c:set
var="foobuzz" value="#{of:concat(testBean.fooman, testBean.buzzman)}"/>
·
both objects are declared non-null in a managed bean named, TestBean
Foo fooman =
new Foo("well-fed", "105kg");
Buzz buzzman
= new Buzz("corpulent", "92kg");
#{foobuzz} -
will
render in all three cases:
Foo is
well-fed, and his weight is 105kg! Buzz is corpulent, and his weight is 92kg!
·
Foo is non-null, Buzz is null
Foo fooman =
new Foo("well-fed", "105kg");
Buzz buzzman
= null;
#{foobuzz} -
In
case of += EL 3.0
operator we will get a java.lang.NullPointerException.
The EL 2.2
concat()
function
and the OmniFaces of:concat() function will render:
Foo is
well-fed, and his weight is 105kg!
Further,
let's try to concatenate the properties of the same object (e.g. Foo):
<c:set
var="foo" value="#{testBean.fooman.foofat.concat(testBean.fooman.fooweight)}"/>
<c:set
var="foo" value="#{testBean.fooman.foofat +=
testBean.fooman.fooweight}"/>
<c:set
var="foo" value="#{of:concat(testBean.fooman.foofat,
testBean.fooman.fooweight)}"/>
·
Foo is non-null, but it contains a null property
Foo fooman =
new Foo("well-fed", null);
#{foo} -
In
case of += EL 3.0
operator we will get a java.lang.NullPointerException.
The EL 2.2
concat()
function
and the OmniFaces of:concat() function will render:
well-fed
Niciun comentariu:
Trimiteți un comentariu