Extracted interface JsonSink.

This commit is contained in:
Benoît Blanchon
2014-06-30 19:19:39 +02:00
parent 81f7849c26
commit 69d682ce81
12 changed files with 171 additions and 214 deletions

View File

@ -37,9 +37,10 @@ private:
JsonValue items[N]; JsonValue items[N];
int itemCount; int itemCount;
virtual void writeTo(StringBuilder& sb) virtual void writeTo(JsonSink& sb)
{ {
sb.append("["); sb.append("[");
sb.reserveRoom(1);
for (int i = 0; i < itemCount; i++) for (int i = 0; i < itemCount; i++)
{ {
@ -47,6 +48,7 @@ private:
items[i].writeTo(sb); items[i].writeTo(sb);
} }
sb.releaseRoom(1);
sb.append("]"); sb.append("]");
} }
}; };

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@ -86,13 +86,13 @@
<ClCompile Include="JsonHashTableTests.cpp" /> <ClCompile Include="JsonHashTableTests.cpp" />
<ClCompile Include="JsonValue.cpp" /> <ClCompile Include="JsonValue.cpp" />
<ClCompile Include="StringBuilder.cpp" /> <ClCompile Include="StringBuilder.cpp" />
<ClCompile Include="StringBuilderAppendEscapedTests.cpp" /> <ClCompile Include="JsonValueTests.cpp" />
<ClCompile Include="StringBuilderAppendTests.cpp" />
</ItemGroup> </ItemGroup>
<ItemGroup> <ItemGroup>
<ClInclude Include="JsonArray.h" /> <ClInclude Include="JsonArray.h" />
<ClInclude Include="JsonHashTable.h" /> <ClInclude Include="JsonHashTable.h" />
<ClInclude Include="JsonObjectBase.h" /> <ClInclude Include="JsonObjectBase.h" />
<ClInclude Include="JsonSink.h" />
<ClInclude Include="JsonValue.h" /> <ClInclude Include="JsonValue.h" />
<ClInclude Include="StringBuilder.h" /> <ClInclude Include="StringBuilder.h" />
</ItemGroup> </ItemGroup>

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@ -21,23 +21,17 @@
<ClCompile Include="StringBuilder.cpp"> <ClCompile Include="StringBuilder.cpp">
<Filter>Source Files</Filter> <Filter>Source Files</Filter>
</ClCompile> </ClCompile>
<ClCompile Include="StringBuilderAppendEscapedTests.cpp">
<Filter>Source Files</Filter>
</ClCompile>
<ClCompile Include="StringBuilderAppendTests.cpp">
<Filter>Source Files</Filter>
</ClCompile>
<ClCompile Include="JsonHashTableTests.cpp"> <ClCompile Include="JsonHashTableTests.cpp">
<Filter>Source Files</Filter> <Filter>Source Files</Filter>
</ClCompile> </ClCompile>
<ClCompile Include="JsonValue.cpp"> <ClCompile Include="JsonValue.cpp">
<Filter>Source Files</Filter> <Filter>Source Files</Filter>
</ClCompile> </ClCompile>
<ClCompile Include="JsonValueTests.cpp">
<Filter>Source Files</Filter>
</ClCompile>
</ItemGroup> </ItemGroup>
<ItemGroup> <ItemGroup>
<ClInclude Include="JsonArray.h">
<Filter>Header Files</Filter>
</ClInclude>
<ClInclude Include="StringBuilder.h"> <ClInclude Include="StringBuilder.h">
<Filter>Header Files</Filter> <Filter>Header Files</Filter>
</ClInclude> </ClInclude>
@ -50,5 +44,11 @@
<ClInclude Include="JsonValue.h"> <ClInclude Include="JsonValue.h">
<Filter>Header Files</Filter> <Filter>Header Files</Filter>
</ClInclude> </ClInclude>
<ClInclude Include="JsonArray.h">
<Filter>Header Files</Filter>
</ClInclude>
<ClInclude Include="JsonSink.h">
<Filter>Header Files</Filter>
</ClInclude>
</ItemGroup> </ItemGroup>
</Project> </Project>

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@ -45,19 +45,24 @@ private:
KeyValuePair items[N]; KeyValuePair items[N];
int itemCount; int itemCount;
virtual void writeTo(StringBuilder& sb) virtual void writeTo(JsonSink& sink)
{ {
sb.append("{"); sink.append("{");
sink.reserveRoom(1);
for (int i = 0; i < itemCount; i++) for (int i = 0; i < itemCount; i++)
{ {
if (i>0) sb.append(","); if (i>0) sink.append(",");
sb.appendEscaped(items[i].key);
sb.append(":"); JsonValue key(items[i].key);
items[i].value.writeTo(sb);
key.writeTo(sink);
sink.append(":");
items[i].value.writeTo(sink);
} }
sb.append("}"); sink.releaseRoom(1);
sink.append("}");
} }
}; };

View File

@ -6,6 +6,7 @@
#pragma once #pragma once
#include "JsonValue.h" #include "JsonValue.h"
#include "JsonSink.h"
class JsonObjectBase class JsonObjectBase
{ {
@ -17,6 +18,6 @@ public:
writeTo(sb); writeTo(sb);
} }
virtual void writeTo(StringBuilder& sb) = 0; virtual void writeTo(JsonSink& sb) = 0;
}; };

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@ -0,0 +1,19 @@
/*
* Arduino JSON library
* Benoit Blanchon 2014 - MIT License
*/
#pragma once
class JsonSink
{
public:
virtual void append(char c) = 0;
virtual void append(const char* s) = 0;
virtual bool hasRoomFor(int n) = 0;
virtual void reserveRoom(int n) = 0;
virtual void releaseRoom(int n) = 0;
};

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@ -5,26 +5,88 @@
#include "JsonValue.h" #include "JsonValue.h"
#include "JsonObjectBase.h" #include "JsonObjectBase.h"
#include <cstdio>
#include <cstring>
void JsonValue::writeBooleanTo(StringBuilder& sb) void JsonValue::writeBooleanTo(JsonSink& sb)
{ {
sb.append(content.boolean ? "true" : "false"); sb.append(content.boolean ? "true" : "false");
} }
void JsonValue::writeNumberTo(StringBuilder& sb) void JsonValue::writeNumberTo(JsonSink& sb)
{ {
sb.append(content.number); char tmp[16];
_snprintf(tmp, sizeof(tmp), "%lg", content.number);
sb.append(tmp);
} }
void JsonValue::writeObjectTo(StringBuilder& sb) void JsonValue::writeObjectTo(JsonSink& sink)
{ {
if (content.object) if (content.object)
((JsonObjectBase*) content.object)->writeTo(sb); ((JsonObjectBase*) content.object)->writeTo(sink);
else else
sb.append("null"); sink.append("null");
} }
void JsonValue::writeStringTo(StringBuilder& sb) void JsonValue::writeStringTo(JsonSink& sink)
{ {
sb.appendEscaped(content.string); auto s = content.string;
if (!s)
{
return sink.append("null");
}
if (!sink.hasRoomFor(2))
{
return;
}
sink.append('\"');
sink.reserveRoom(1);
while (*s)
{
switch (*s)
{
case '"':
sink.append("\\\"");
break;
case '\\':
sink.append("\\\\");
break;
case '\b':
sink.append("\\b");
break;
case '\f':
sink.append("\\f");
break;
case '\n':
sink.append("\\n");
break;
case '\r':
sink.append("\\r");
break;
case '\t':
sink.append("\\t");
break;
default:
sink.append(*s);
break;
}
s++;
}
sink.releaseRoom(1);
sink.append('\"');
} }

View File

@ -41,10 +41,10 @@ public:
content.object = &value; content.object = &value;
} }
void writeTo(StringBuilder& sb) void writeTo(JsonSink& sink)
{ {
// handmade polymorphism // handmade polymorphism
(this->*implementation)(sb); (this->*implementation)(sink);
} }
private: private:
@ -59,10 +59,10 @@ private:
Content content; Content content;
void (JsonValue::*implementation)(StringBuilder& sb); void (JsonValue::*implementation)(JsonSink& sb);
void writeBooleanTo(StringBuilder& sb); void writeBooleanTo(JsonSink& sb);
void writeNumberTo(StringBuilder& sb); void writeNumberTo(JsonSink& sb);
void writeObjectTo(StringBuilder& sb); void writeObjectTo(JsonSink& sb);
void writeStringTo(StringBuilder& sb); void writeStringTo(JsonSink& sb);
}; };

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@ -1,11 +1,12 @@
#include "CppUnitTest.h" #include "CppUnitTest.h"
#include "StringBuilder.h" #include "StringBuilder.h"
#include "JsonValue.h"
using namespace Microsoft::VisualStudio::CppUnitTestFramework; using namespace Microsoft::VisualStudio::CppUnitTestFramework;
namespace JsonGeneratorTests namespace JsonGeneratorTests
{ {
TEST_CLASS(StringBuilderAppendEscapedTests) TEST_CLASS(JsonValueTests)
{ {
char buffer[20]; char buffer[20];
StringBuilder* sb; StringBuilder* sb;
@ -16,24 +17,24 @@ namespace JsonGeneratorTests
{ {
sb = new StringBuilder(buffer, sizeof(buffer)); sb = new StringBuilder(buffer, sizeof(buffer));
} }
TEST_METHOD(InitialState) TEST_METHOD(InitialState)
{ {
assertResultIs(""); assertResultIs("");
} }
TEST_METHOD(Null)
{
append((char*)0);
assertResultIs("null");
}
TEST_METHOD(EmptyString) TEST_METHOD(EmptyString)
{ {
append(""); append("");
assertResultIs("\"\""); assertResultIs("\"\"");
} }
TEST_METHOD(Null)
{
append(NULL);
assertResultIs("null");
}
TEST_METHOD(OneString) TEST_METHOD(OneString)
{ {
append("ABCD"); append("ABCD");
@ -55,16 +56,23 @@ namespace JsonGeneratorTests
append(""); append("");
assertResultIs("\"ABCDEFGHIJKLMNOPQ\""); assertResultIs("\"ABCDEFGHIJKLMNOPQ\"");
} }
TEST_METHOD(SpecialChars) TEST_METHOD(SpecialChars)
{ {
append("\\\"\b\f\n\r\t"); append("\\\"\b\f\n\r\t");
assertResultIs("\"\\\\\\\"\\b\\f\\n\\r\\t\""); assertResultIs("\"\\\\\\\"\\b\\f\\n\\r\\t\"");
} }
void append(const char* s) TEST_METHOD(Number)
{ {
sb->appendEscaped(s); append(3.14);
assertResultIs("3.14");
}
template<typename T>
void append(T value)
{
JsonValue(value).writeTo(*sb);
} }
void assertResultIs(const char* expected) void assertResultIs(const char* expected)

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@ -3,27 +3,10 @@
* Benoit Blanchon 2014 - MIT License * Benoit Blanchon 2014 - MIT License
*/ */
#include <cstdio>
#include <cstring>
#include "StringBuilder.h" #include "StringBuilder.h"
void StringBuilder::append(double value)
{
char* tail = buffer + length;
_snprintf(tail, capacity - length, "%lg", value);
length += strlen(tail);
}
void StringBuilder::append(const char* s) void StringBuilder::append(const char* s)
{ {
if (!s)
{
return append("null");
}
char* tail = buffer + length; char* tail = buffer + length;
while (*s && length<capacity) while (*s && length<capacity)
@ -34,67 +17,11 @@ void StringBuilder::append(const char* s)
buffer[length] = 0; buffer[length] = 0;
} }
void StringBuilder::appendEscaped(const char* s)
void StringBuilder::append(char c)
{ {
if (!s) if (length >= capacity) return;
{
return append("null");
}
if (length > capacity - 2) buffer[length++] = c;
{
// not enough from for quotes
return;
}
buffer[length++] = '"';
// keep one slot for the end quote
capacity--;
while (*s && length < capacity)
{
switch (*s)
{
case '"':
append("\\\"");
break;
case '\\':
append("\\\\");
break;
case '\b':
append("\\b");
break;
case '\f':
append("\\f");
break;
case '\n':
append("\\n");
break;
case '\r':
append("\\r");
break;
case '\t':
append("\\t");
break;
default:
buffer[length++] = *s;
break;
}
s++;
}
buffer[length++] = '"';
buffer[length] = 0; buffer[length] = 0;
// restore the original capacity
capacity++;
} }

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@ -5,22 +5,38 @@
#pragma once #pragma once
class StringBuilder #include "JsonSink.h"
class StringBuilder : public JsonSink
{ {
public: public:
StringBuilder(char* buf, size_t size) StringBuilder(char* buf, int size)
: buffer(buf), capacity(size-1), length(0) : buffer(buf), capacity(size-1), length(0)
{ {
buffer[0] = 0; buffer[0] = 0;
} }
void append(double); virtual void append(char c);
void append(const char* s); virtual void append(const char* s);
void appendEscaped(const char* s);
virtual bool hasRoomFor(int n)
{
return capacity - length >= n;
}
virtual void reserveRoom(int n)
{
capacity -= n;
}
virtual void releaseRoom(int n)
{
capacity += n;
}
private: private:
char* buffer; char* buffer;
size_t capacity; int capacity;
size_t length; int length;
}; };

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@ -1,83 +0,0 @@
#include "CppUnitTest.h"
#include "StringBuilder.h"
using namespace Microsoft::VisualStudio::CppUnitTestFramework;
namespace JsonGeneratorTests
{
TEST_CLASS(StringBuilderAppendTests)
{
char buffer[16];
StringBuilder* sb;
public:
TEST_METHOD_INITIALIZE(Initialize)
{
sb = new StringBuilder(buffer, sizeof(buffer));
}
TEST_METHOD(InitialState)
{
assertResultIs("");
}
TEST_METHOD(EmptyString)
{
append("");
assertResultIs("");
}
TEST_METHOD(Null)
{
append((char*)0);
assertResultIs("null");
}
TEST_METHOD(Number)
{
append(3.14);
assertResultIs("3.14");
}
TEST_METHOD(OneString)
{
append("ABCD");
assertResultIs("ABCD");
}
TEST_METHOD(TwoStrings)
{
append("ABCD");
append("EFGH");
assertResultIs("ABCDEFGH");
}
TEST_METHOD(OverCapacity)
{
append("ABCDEFGHIJKLMNOPQRSTUVWXYZ");
assertResultIs("ABCDEFGHIJKLMNO");
}
TEST_METHOD(SpecialChars)
{
append("\\\"\b\f\n\r");
assertResultIs("\\\"\b\f\n\r");
}
void append(double d)
{
sb->append(d);
}
void append(const char* s)
{
sb->append(s);
}
void assertResultIs(const char* expected)
{
Assert::AreEqual(expected, buffer);
}
};
}