add getValue() overloads that return true/false rather than throwing

mdaus · Dec 22, 2020 · 1aa458e · 1aa458e
1 parent faa6d30
commit 1aa458e
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Showing 2 changed files with 72 additions and 16 deletions.
diff --git a/modules/c++/xml.lite/include/xml/lite/Attributes.h b/modules/c++/xml.lite/include/xml/lite/Attributes.h
@@ -22,6 +22,7 @@
 
 #ifndef __XML_LITE_ATTRIBUTES_H__
 #define __XML_LITE_ATTRIBUTES_H__
+#pragma once
 
 #include "sys/Conf.h"
 #include "except/Exception.h"
@@ -172,7 +173,7 @@ class Attributes
      *  Adds an attribute to the list of attributes.
      *  \param attribute the attribute to add
      */
-    void add(const AttributeNode & attribute);
+    AttributeNode& add(const AttributeNode& attribute);
 
     /*!
      * Look up the index of an attribute by XML 1.0 qualified name.
@@ -223,6 +224,13 @@ class Attributes
      * \throw IndexOutOfRangeException if the index is out of range
      */
     std::string getValue(int i) const;
+    /*!
+     * Look up an attribute's value by index.
+     * \param i  The index for the attribute we want
+     * \param result The value, if found
+     * \return If the index is out of range or not
+     */
+    bool getValue(int i, std::string& result) const;
 
     /*!
      * Look up an attribute's value by XML 1.0 qualified name.
@@ -231,16 +239,32 @@ class Attributes
      * \throw NoSuchKeyException If the qname is not found
      */
     std::string getValue(const std::string & qname) const;
+    /*!
+     * Look up an attribute's value by XML 1.0 qualified name.
+     * \param qname The qualified name
+     * \param result The value, if found
+     * \return If the qname is not found or not
+     */
+    bool getValue(const std::string& qname, std::string& result) const;
 
     /*!
      * Look up an attribute's value by Namespace name.
      * \param uri The uri association
      * \param localName the local name of the object
      * \return The value
-     * \throw NoSuchKeyException If the qname is not found
+     * \throw NoSuchKeyException If the uri/localName is not found
      */
-    std::string getValue(const std::string & uri,
-                         const std::string & localName) const;
+    std::string getValue(const std::string & uri, const std::string & localName) const;
+    /*!
+     * Look up an attribute's value by Namespace name.
+     * \param uri The uri association
+     * \param localName the local name of the object
+     * \param result The value, if found
+     * \return If the uri/localName is not found or not
+     */
+    bool getValue(const std::string& uri, const std::string& localName,
+        std::string& result) const;
+
     /*!
      * Get an attribute note based on the index as a const ref
      * \param i The node index

diff --git a/modules/c++/xml.lite/source/Attributes.cpp b/modules/c++/xml.lite/source/Attributes.cpp
@@ -65,6 +65,15 @@ std::string xml::lite::Attributes::getValue(int i) const
 {
     return mAttributes.at(i).getValue();
 }
+bool xml::lite::Attributes::getValue(int i, std::string& result) const
+{
+    if ((i >= 0) && (i < mAttributes.size()))
+    {
+        result = mAttributes[i].getValue();
+        return true; // index in range
+    }
+    return false; // index out-of-range
+}
 
 std::string xml::lite::Attributes::getUri(int i) const
 {
@@ -82,39 +91,62 @@ std::string xml::lite::Attributes::getQName(int i) const
 }
 
 std::string xml::lite::Attributes::getValue(const std::string& qname) const
+{
+    std::string retval;
+    if (!getValue(qname, retval))
+    {
+        throw except::NoSuchKeyException(Ctxt(FmtX("QName '%s' could not be found",
+                                                   qname.c_str())));
+    }
+
+    return retval;  
+}
 {
     for (size_t i = 0; i < mAttributes.size(); i++)
     {
         if (qname == mAttributes[i].getQName())
-            return mAttributes[i].getValue();
+        {
+            result = mAttributes[i].getValue();
+            return true; // found
+        }
     }
-    throw except::NoSuchKeyException(Ctxt(FmtX("QName '%s' could not be found",
-                                               qname.c_str())));
 
-    // We don't ever reach this but it keeps the compiler from complaining...
-    return mAttributes[mAttributes.size() - 1].getValue();
+    return false; // not found
 }
 
 std::string xml::lite::Attributes::getValue(
     const std::string& uri,
     const std::string& localName) const
+{
+    std::string retval;
+    if (!getValue(uri, localName, retval))
+    {
+        throw except::NoSuchKeyException(Ctxt(FmtX("(uri: %s, localName: %s",
+                                                   uri.c_str(), localName.c_str())));
+    }
+    return retval;
+}
+bool xml::lite::Attributes::getValue(
+    const std::string& uri,
+    const std::string& localName,
+    std::string& result) const
 {
     for (size_t i = 0; i < mAttributes.size(); i++)
     {
         if ((uri == mAttributes[i].getUri()) && (localName
                 == mAttributes[i].getLocalName()))
-            return mAttributes[i].getValue();
+        {
+            result = mAttributes[i].getValue();
+            return true; // found
+        }
     }
-    throw except::NoSuchKeyException(Ctxt(FmtX("(uri: %s, localName: %s",
-                                               uri.c_str(), localName.c_str())));
-
-    // We don't ever reach this but it keeps the compiler from complaining...
-    return mAttributes[mAttributes.size() - 1].getValue();
+    return false; // not found
 }
 
-void xml::lite::Attributes::add(const AttributeNode& attribute)
+xml::lite::AttributeNode& xml::lite::Attributes::add(const AttributeNode& attribute)
 {
     mAttributes.push_back(attribute);
+    return mAttributes.back();
 }
 
 void xml::lite::AttributeNode::setQName(const std::string& qname)