XSD element validation

[Ketan KC Chachad]

What does one need to specify in an XSD element tag to ensure that the corresponding XML tag cannot contain null/blank values? For example if I have the following XML document

<?xml version="1.0" encoding="UTF-8"?>
<properties xmlns:xsi="http://www.w3.org/2001/XMLSchema-instance"
xsi:noNamespaceSchemaLocation="properties.xsd">
<property>
<name>length</name>
<value>30</value>
<type>int</type>
<format></format>
<mandatory>true</mandatory>
</property>
</properties>

Then in XSD what do I write for the name element so that it cannot contain a null/blank values. My current XSD looks like as follows:

<?xml version="1.0" encoding="UTF-8"?>
<xs:schema xmlns:xs="http://www.w3.org/2001/XMLSchema" >
 
<xs:element name="properties">
<xs:complexType>
<xs:sequence>
<xs:element ref="property" minOccurs="1" maxOccurs="unbounded" />
</xs:sequence>
</xs:complexType>
</xs:element>
 
<xs:element name="property">
<xs:complexType>
<xs:sequence>
<xs:element ref="name" minOccurs="1" maxOccurs="1"/>
<xs:element name="value" type="xs:string" minOccurs="1" maxOccurs="1" />
<xs:element ref="type" minOccurs="1" maxOccurs="1"/>
<xs:element name="format" type="xs:string" minOccurs="1" maxOccurs="1" />
<xs:element ref="mandatory" minOccurs="0" maxOccurs="1"/>
</xs:sequence>
</xs:complexType>
</xs:element>
 
<xs:element name="name">
<xs:simpleType>
<xs:restriction base="xs:string">
<xs:pattern value="([a-zA-Z])+"/>
</xs:restriction>
</xs:simpleType>
</xs:element>
 
<xs:element name="type">
<xs:simpleType>
<xs:restriction base="xs:string">
<xs:enumeration value="int" />
<xs:enumeration value="datetime" />
<xs:enumeration value="string" />
<xs:enumeration value="boolean" />
<xs:enumeration value="double" />
</xs:restriction>
</xs:simpleType>
</xs:element>
 
<xs:element name="mandatory" default="false">
<xs:simpleType>
<xs:restriction base="xs:boolean" />
</xs:simpleType>
</xs:element>
 
</xs:schema>

[Ketan KC Chachad]

The error messages listed below are those caught and stored in a SAXParserException object

cvc-type.3.1.3

cvc-enumeration-valid

cvc-complex-type.2.4.a

cvc-datatype-valid.1.2.1

cvc-pattern-valid

I would also like to know where I can find out the complete listing of all possible validation error messages that are thrown by the validator class.