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TypeAdapter (Gson 2.3.1 API)
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com.google.gson</FONT>
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Class TypeAdapter<T></H2>
<PRE>
<A HREF="http://docs.oracle.com/javase/1.5.0/docs/api/java/lang/Object.html?is-external=true" title="class or interface in java.lang">java.lang.Object</A>
<IMG SRC="../../../resources/inherit.gif" ALT="extended by "><B>com.google.gson.TypeAdapter<T></B>
</PRE>
<HR>
<DL>
<DT><PRE>public abstract class <B>TypeAdapter<T></B><DT>extends <A HREF="http://docs.oracle.com/javase/1.5.0/docs/api/java/lang/Object.html?is-external=true" title="class or interface in java.lang">Object</A></DL>
</PRE>
<P>
Converts Java objects to and from JSON.
<h3>Defining a type's JSON form</h3>
By default Gson converts application classes to JSON using its built-in type
adapters. If Gson's default JSON conversion isn't appropriate for a type,
extend this class to customize the conversion. Here's an example of a type
adapter for an (X,Y) coordinate point: <pre> <code>public class PointAdapter extends TypeAdapter<Point> {
public Point read(JsonReader reader) throws IOException {
if (reader.peek() == JsonToken.NULL) {
reader.nextNull();
return null;
}
String xy = reader.nextString();
String[] parts = xy.split(",");
int x = Integer.parseInt(parts[0]);
int y = Integer.parseInt(parts[1]);
return new Point(x, y);
}
public void write(JsonWriter writer, Point value) throws IOException {
if (value == null) {
writer.nullValue();
return;
}
String xy = value.getX() + "," + value.getY();
writer.value(xy);
}
}</code></pre>
With this type adapter installed, Gson will convert <code>Points</code> to JSON as
strings like <code>"5,8"</code> rather than objects like <code>{"x":5,"y":8}</code>. In
this case the type adapter binds a rich Java class to a compact JSON value.
<p>The <A HREF="../../../com/google/gson/TypeAdapter.html#read(com.google.gson.stream.JsonReader)"><CODE>read()</CODE></A> method must read exactly one value
and <A HREF="../../../com/google/gson/TypeAdapter.html#write(com.google.gson.stream.JsonWriter, T)"><CODE>write()</CODE></A> must write exactly one value.
For primitive types this is means readers should make exactly one call to
<code>nextBoolean()</code>, <code>nextDouble()</code>, <code>nextInt()</code>, <code>nextLong()</code>, <code>nextString()</code> or <code>nextNull()</code>. Writers should make
exactly one call to one of <code>value()</code> or <code>nullValue()</code>.
For arrays, type adapters should start with a call to <code>beginArray()</code>,
convert all elements, and finish with a call to <code>endArray()</code>. For
objects, they should start with <code>beginObject()</code>, convert the object,
and finish with <code>endObject()</code>. Failing to convert a value or converting
too many values may cause the application to crash.
<p>Type adapters should be prepared to read null from the stream and write it
to the stream. Alternatively, they should use <A HREF="../../../com/google/gson/TypeAdapter.html#nullSafe()"><CODE>nullSafe()</CODE></A> method while
registering the type adapter with Gson. If your <code>Gson</code> instance
has been configured to <A HREF="../../../com/google/gson/GsonBuilder.html#serializeNulls()"><CODE>GsonBuilder.serializeNulls()</CODE></A>, these nulls will be
written to the final document. Otherwise the value (and the corresponding name
when writing to a JSON object) will be omitted automatically. In either case
your type adapter must handle null.
<p>To use a custom type adapter with Gson, you must <i>register</i> it with a
<A HREF="../../../com/google/gson/GsonBuilder.html" title="class in com.google.gson"><CODE>GsonBuilder</CODE></A>: <pre> <code>GsonBuilder builder = new GsonBuilder();
builder.registerTypeAdapter(Point.class, new PointAdapter());
// if PointAdapter didn't check for nulls in its read/write methods, you should instead use
// builder.registerTypeAdapter(Point.class, new PointAdapter().nullSafe());
...
Gson gson = builder.create();
</code></pre>
<P>
<P>
<DL>
<DT><B>Since:</B></DT>
<DD>2.1</DD>
</DL>
<HR>
<P>
<!-- ======== CONSTRUCTOR SUMMARY ======== -->
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<B>Constructor Summary</B></FONT></TH>
</TR>
<TR BGCOLOR="white" CLASS="TableRowColor">
<TD><CODE><B><A HREF="../../../com/google/gson/TypeAdapter.html#TypeAdapter()">TypeAdapter</A></B>()</CODE>
<BR>
</TD>
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<!-- ========== METHOD SUMMARY =========== -->
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<TH ALIGN="left" COLSPAN="2"><FONT SIZE="+2">
<B>Method Summary</B></FONT></TH>
</TR>
<TR BGCOLOR="white" CLASS="TableRowColor">
<TD ALIGN="right" VALIGN="top" WIDTH="1%"><FONT SIZE="-1">
<CODE> <A HREF="../../../com/google/gson/TypeAdapter.html" title="type parameter in TypeAdapter">T</A></CODE></FONT></TD>
<TD><CODE><B><A HREF="../../../com/google/gson/TypeAdapter.html#fromJson(java.io.Reader)">fromJson</A></B>(<A HREF="http://docs.oracle.com/javase/1.5.0/docs/api/java/io/Reader.html?is-external=true" title="class or interface in java.io">Reader</A> in)</CODE>
<BR>
Converts the JSON document in <code>in</code> to a Java object.</TD>
</TR>
<TR BGCOLOR="white" CLASS="TableRowColor">
<TD ALIGN="right" VALIGN="top" WIDTH="1%"><FONT SIZE="-1">
<CODE> <A HREF="../../../com/google/gson/TypeAdapter.html" title="type parameter in TypeAdapter">T</A></CODE></FONT></TD>
<TD><CODE><B><A HREF="../../../com/google/gson/TypeAdapter.html#fromJson(java.lang.String)">fromJson</A></B>(<A HREF="http://docs.oracle.com/javase/1.5.0/docs/api/java/lang/String.html?is-external=true" title="class or interface in java.lang">String</A> json)</CODE>
<BR>
Converts the JSON document in <code>json</code> to a Java object.</TD>
</TR>
<TR BGCOLOR="white" CLASS="TableRowColor">
<TD ALIGN="right" VALIGN="top" WIDTH="1%"><FONT SIZE="-1">
<CODE> <A HREF="../../../com/google/gson/TypeAdapter.html" title="type parameter in TypeAdapter">T</A></CODE></FONT></TD>
<TD><CODE><B><A HREF="../../../com/google/gson/TypeAdapter.html#fromJsonTree(com.google.gson.JsonElement)">fromJsonTree</A></B>(<A HREF="../../../com/google/gson/JsonElement.html" title="class in com.google.gson">JsonElement</A> jsonTree)</CODE>
<BR>
Converts <code>jsonTree</code> to a Java object.</TD>
</TR>
<TR BGCOLOR="white" CLASS="TableRowColor">
<TD ALIGN="right" VALIGN="top" WIDTH="1%"><FONT SIZE="-1">
<CODE> <A HREF="../../../com/google/gson/TypeAdapter.html" title="class in com.google.gson">TypeAdapter</A><<A HREF="../../../com/google/gson/TypeAdapter.html" title="type parameter in TypeAdapter">T</A>></CODE></FONT></TD>
<TD><CODE><B><A HREF="../../../com/google/gson/TypeAdapter.html#nullSafe()">nullSafe</A></B>()</CODE>
<BR>
This wrapper method is used to make a type adapter null tolerant.</TD>
</TR>
<TR BGCOLOR="white" CLASS="TableRowColor">
<TD ALIGN="right" VALIGN="top" WIDTH="1%"><FONT SIZE="-1">
<CODE>abstract <A HREF="../../../com/google/gson/TypeAdapter.html" title="type parameter in TypeAdapter">T</A></CODE></FONT></TD>
<TD><CODE><B><A HREF="../../../com/google/gson/TypeAdapter.html#read(com.google.gson.stream.JsonReader)">read</A></B>(<A HREF="../../../com/google/gson/stream/JsonReader.html" title="class in com.google.gson.stream">JsonReader</A> in)</CODE>
<BR>
Reads one JSON value (an array, object, string, number, boolean or null)
and converts it to a Java object.</TD>
</TR>
<TR BGCOLOR="white" CLASS="TableRowColor">
<TD ALIGN="right" VALIGN="top" WIDTH="1%"><FONT SIZE="-1">
<CODE> <A HREF="http://docs.oracle.com/javase/1.5.0/docs/api/java/lang/String.html?is-external=true" title="class or interface in java.lang">String</A></CODE></FONT></TD>
<TD><CODE><B><A HREF="../../../com/google/gson/TypeAdapter.html#toJson(T)">toJson</A></B>(<A HREF="../../../com/google/gson/TypeAdapter.html" title="type parameter in TypeAdapter">T</A> value)</CODE>
<BR>
Converts <code>value</code> to a JSON document.</TD>
</TR>
<TR BGCOLOR="white" CLASS="TableRowColor">
<TD ALIGN="right" VALIGN="top" WIDTH="1%"><FONT SIZE="-1">
<CODE> void</CODE></FONT></TD>
<TD><CODE><B><A HREF="../../../com/google/gson/TypeAdapter.html#toJson(java.io.Writer, T)">toJson</A></B>(<A HREF="http://docs.oracle.com/javase/1.5.0/docs/api/java/io/Writer.html?is-external=true" title="class or interface in java.io">Writer</A> out,
<A HREF="../../../com/google/gson/TypeAdapter.html" title="type parameter in TypeAdapter">T</A> value)</CODE>
<BR>
Converts <code>value</code> to a JSON document and writes it to <code>out</code>.</TD>
</TR>
<TR BGCOLOR="white" CLASS="TableRowColor">
<TD ALIGN="right" VALIGN="top" WIDTH="1%"><FONT SIZE="-1">
<CODE> <A HREF="../../../com/google/gson/JsonElement.html" title="class in com.google.gson">JsonElement</A></CODE></FONT></TD>
<TD><CODE><B><A HREF="../../../com/google/gson/TypeAdapter.html#toJsonTree(T)">toJsonTree</A></B>(<A HREF="../../../com/google/gson/TypeAdapter.html" title="type parameter in TypeAdapter">T</A> value)</CODE>
<BR>
Converts <code>value</code> to a JSON tree.</TD>
</TR>
<TR BGCOLOR="white" CLASS="TableRowColor">
<TD ALIGN="right" VALIGN="top" WIDTH="1%"><FONT SIZE="-1">
<CODE>abstract void</CODE></FONT></TD>
<TD><CODE><B><A HREF="../../../com/google/gson/TypeAdapter.html#write(com.google.gson.stream.JsonWriter, T)">write</A></B>(<A HREF="../../../com/google/gson/stream/JsonWriter.html" title="class in com.google.gson.stream">JsonWriter</A> out,
<A HREF="../../../com/google/gson/TypeAdapter.html" title="type parameter in TypeAdapter">T</A> value)</CODE>
<BR>
Writes one JSON value (an array, object, string, number, boolean or null)
for <code>value</code>.</TD>
</TR>
</TABLE>
<A NAME="methods_inherited_from_class_java.lang.Object"><!-- --></A>
<TABLE BORDER="1" WIDTH="100%" CELLPADDING="3" CELLSPACING="0" SUMMARY="">
<TR BGCOLOR="#EEEEFF" CLASS="TableSubHeadingColor">
<TH ALIGN="left"><B>Methods inherited from class java.lang.<A HREF="http://docs.oracle.com/javase/1.5.0/docs/api/java/lang/Object.html?is-external=true" title="class or interface in java.lang">Object</A></B></TH>
</TR>
<TR BGCOLOR="white" CLASS="TableRowColor">
<TD><CODE><A HREF="http://docs.oracle.com/javase/1.5.0/docs/api/java/lang/Object.html?is-external=true#clone()" title="class or interface in java.lang">clone</A>, <A HREF="http://docs.oracle.com/javase/1.5.0/docs/api/java/lang/Object.html?is-external=true#equals(java.lang.Object)" title="class or interface in java.lang">equals</A>, <A HREF="http://docs.oracle.com/javase/1.5.0/docs/api/java/lang/Object.html?is-external=true#finalize()" title="class or interface in java.lang">finalize</A>, <A HREF="http://docs.oracle.com/javase/1.5.0/docs/api/java/lang/Object.html?is-external=true#getClass()" title="class or interface in java.lang">getClass</A>, <A HREF="http://docs.oracle.com/javase/1.5.0/docs/api/java/lang/Object.html?is-external=true#hashCode()" title="class or interface in java.lang">hashCode</A>, <A HREF="http://docs.oracle.com/javase/1.5.0/docs/api/java/lang/Object.html?is-external=true#notify()" title="class or interface in java.lang">notify</A>, <A HREF="http://docs.oracle.com/javase/1.5.0/docs/api/java/lang/Object.html?is-external=true#notifyAll()" title="class or interface in java.lang">notifyAll</A>, <A HREF="http://docs.oracle.com/javase/1.5.0/docs/api/java/lang/Object.html?is-external=true#toString()" title="class or interface in java.lang">toString</A>, <A HREF="http://docs.oracle.com/javase/1.5.0/docs/api/java/lang/Object.html?is-external=true#wait()" title="class or interface in java.lang">wait</A>, <A HREF="http://docs.oracle.com/javase/1.5.0/docs/api/java/lang/Object.html?is-external=true#wait(long)" title="class or interface in java.lang">wait</A>, <A HREF="http://docs.oracle.com/javase/1.5.0/docs/api/java/lang/Object.html?is-external=true#wait(long, int)" title="class or interface in java.lang">wait</A></CODE></TD>
</TR>
</TABLE>
<P>
<!-- ========= CONSTRUCTOR DETAIL ======== -->
<A NAME="constructor_detail"><!-- --></A>
<TABLE BORDER="1" WIDTH="100%" CELLPADDING="3" CELLSPACING="0" SUMMARY="">
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<B>Constructor Detail</B></FONT></TH>
</TR>
</TABLE>
<A NAME="TypeAdapter()"><!-- --></A><H3>
TypeAdapter</H3>
<PRE>
public <B>TypeAdapter</B>()</PRE>
<DL>
</DL>
<!-- ============ METHOD DETAIL ========== -->
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<B>Method Detail</B></FONT></TH>
</TR>
</TABLE>
<A NAME="write(com.google.gson.stream.JsonWriter,java.lang.Object)"><!-- --></A><A NAME="write(com.google.gson.stream.JsonWriter, T)"><!-- --></A><H3>
write</H3>
<PRE>
public abstract void <B>write</B>(<A HREF="../../../com/google/gson/stream/JsonWriter.html" title="class in com.google.gson.stream">JsonWriter</A> out,
<A HREF="../../../com/google/gson/TypeAdapter.html" title="type parameter in TypeAdapter">T</A> value)
throws <A HREF="http://docs.oracle.com/javase/1.5.0/docs/api/java/io/IOException.html?is-external=true" title="class or interface in java.io">IOException</A></PRE>
<DL>
<DD>Writes one JSON value (an array, object, string, number, boolean or null)
for <code>value</code>.
<P>
<DD><DL>
<DT><B>Parameters:</B><DD><CODE>value</CODE> - the Java object to write. May be null.
<DT><B>Throws:</B>
<DD><CODE><A HREF="http://docs.oracle.com/javase/1.5.0/docs/api/java/io/IOException.html?is-external=true" title="class or interface in java.io">IOException</A></CODE></DL>
</DD>
</DL>
<HR>
<A NAME="toJson(java.io.Writer,java.lang.Object)"><!-- --></A><A NAME="toJson(java.io.Writer, T)"><!-- --></A><H3>
toJson</H3>
<PRE>
public final void <B>toJson</B>(<A HREF="http://docs.oracle.com/javase/1.5.0/docs/api/java/io/Writer.html?is-external=true" title="class or interface in java.io">Writer</A> out,
<A HREF="../../../com/google/gson/TypeAdapter.html" title="type parameter in TypeAdapter">T</A> value)
throws <A HREF="http://docs.oracle.com/javase/1.5.0/docs/api/java/io/IOException.html?is-external=true" title="class or interface in java.io">IOException</A></PRE>
<DL>
<DD>Converts <code>value</code> to a JSON document and writes it to <code>out</code>.
Unlike Gson's similar <A HREF="../../../com/google/gson/Gson.html#toJson(com.google.gson.JsonElement, java.lang.Appendable)"><CODE>toJson</CODE></A>
method, this write is strict. Create a <A HREF="../../../com/google/gson/stream/JsonWriter.html#setLenient(boolean)"><CODE>lenient</CODE></A> <code>JsonWriter</code> and call
<A HREF="../../../com/google/gson/TypeAdapter.html#write(com.google.gson.stream.JsonWriter, T)"><CODE>write(com.google.gson.stream.JsonWriter, Object)</CODE></A> for lenient
writing.
<P>
<DD><DL>
<DT><B>Parameters:</B><DD><CODE>value</CODE> - the Java object to convert. May be null.
<DT><B>Throws:</B>
<DD><CODE><A HREF="http://docs.oracle.com/javase/1.5.0/docs/api/java/io/IOException.html?is-external=true" title="class or interface in java.io">IOException</A></CODE><DT><B>Since:</B></DT>
<DD>2.2</DD>
</DL>
</DD>
</DL>
<HR>
<A NAME="nullSafe()"><!-- --></A><H3>
nullSafe</H3>
<PRE>
public final <A HREF="../../../com/google/gson/TypeAdapter.html" title="class in com.google.gson">TypeAdapter</A><<A HREF="../../../com/google/gson/TypeAdapter.html" title="type parameter in TypeAdapter">T</A>> <B>nullSafe</B>()</PRE>
<DL>
<DD>This wrapper method is used to make a type adapter null tolerant. In general, a
type adapter is required to handle nulls in write and read methods. Here is how this
is typically done:<br>
<pre> <code>Gson gson = new GsonBuilder().registerTypeAdapter(Foo.class,
new TypeAdapter<Foo>() {
public Foo read(JsonReader in) throws IOException {
if (in.peek() == JsonToken.NULL) {
in.nextNull();
return null;
}
// read a Foo from in and return it
}
public void write(JsonWriter out, Foo src) throws IOException {
if (src == null) {
out.nullValue();
return;
}
// write src as JSON to out
}
}).create();
</code></pre>
You can avoid this boilerplate handling of nulls by wrapping your type adapter with
this method. Here is how we will rewrite the above example:
<pre> <code>Gson gson = new GsonBuilder().registerTypeAdapter(Foo.class,
new TypeAdapter<Foo>() {
public Foo read(JsonReader in) throws IOException {
// read a Foo from in and return it
}
public void write(JsonWriter out, Foo src) throws IOException {
// write src as JSON to out
}
}.nullSafe()).create();
</code></pre>
Note that we didn't need to check for nulls in our type adapter after we used nullSafe.
<P>
<DD><DL>
</DL>
</DD>
</DL>
<HR>
<A NAME="toJson(java.lang.Object)"><!-- --></A><A NAME="toJson(T)"><!-- --></A><H3>
toJson</H3>
<PRE>
public final <A HREF="http://docs.oracle.com/javase/1.5.0/docs/api/java/lang/String.html?is-external=true" title="class or interface in java.lang">String</A> <B>toJson</B>(<A HREF="../../../com/google/gson/TypeAdapter.html" title="type parameter in TypeAdapter">T</A> value)
throws <A HREF="http://docs.oracle.com/javase/1.5.0/docs/api/java/io/IOException.html?is-external=true" title="class or interface in java.io">IOException</A></PRE>
<DL>
<DD>Converts <code>value</code> to a JSON document. Unlike Gson's similar <A HREF="../../../com/google/gson/Gson.html#toJson(java.lang.Object)"><CODE>toJson</CODE></A> method, this write is strict. Create a <A HREF="../../../com/google/gson/stream/JsonWriter.html#setLenient(boolean)"><CODE>lenient</CODE></A> <code>JsonWriter</code> and call
<A HREF="../../../com/google/gson/TypeAdapter.html#write(com.google.gson.stream.JsonWriter, T)"><CODE>write(com.google.gson.stream.JsonWriter, Object)</CODE></A> for lenient
writing.
<P>
<DD><DL>
<DT><B>Parameters:</B><DD><CODE>value</CODE> - the Java object to convert. May be null.
<DT><B>Throws:</B>
<DD><CODE><A HREF="http://docs.oracle.com/javase/1.5.0/docs/api/java/io/IOException.html?is-external=true" title="class or interface in java.io">IOException</A></CODE><DT><B>Since:</B></DT>
<DD>2.2</DD>
</DL>
</DD>
</DL>
<HR>
<A NAME="toJsonTree(java.lang.Object)"><!-- --></A><A NAME="toJsonTree(T)"><!-- --></A><H3>
toJsonTree</H3>
<PRE>
public final <A HREF="../../../com/google/gson/JsonElement.html" title="class in com.google.gson">JsonElement</A> <B>toJsonTree</B>(<A HREF="../../../com/google/gson/TypeAdapter.html" title="type parameter in TypeAdapter">T</A> value)</PRE>
<DL>
<DD>Converts <code>value</code> to a JSON tree.
<P>
<DD><DL>
<DT><B>Parameters:</B><DD><CODE>value</CODE> - the Java object to convert. May be null.
<DT><B>Returns:</B><DD>the converted JSON tree. May be <A HREF="../../../com/google/gson/JsonNull.html" title="class in com.google.gson"><CODE>JsonNull</CODE></A>.<DT><B>Since:</B></DT>
<DD>2.2</DD>
</DL>
</DD>
</DL>
<HR>
<A NAME="read(com.google.gson.stream.JsonReader)"><!-- --></A><H3>
read</H3>
<PRE>
public abstract <A HREF="../../../com/google/gson/TypeAdapter.html" title="type parameter in TypeAdapter">T</A> <B>read</B>(<A HREF="../../../com/google/gson/stream/JsonReader.html" title="class in com.google.gson.stream">JsonReader</A> in)
throws <A HREF="http://docs.oracle.com/javase/1.5.0/docs/api/java/io/IOException.html?is-external=true" title="class or interface in java.io">IOException</A></PRE>
<DL>
<DD>Reads one JSON value (an array, object, string, number, boolean or null)
and converts it to a Java object. Returns the converted object.
<P>
<DD><DL>
<DT><B>Returns:</B><DD>the converted Java object. May be null.
<DT><B>Throws:</B>
<DD><CODE><A HREF="http://docs.oracle.com/javase/1.5.0/docs/api/java/io/IOException.html?is-external=true" title="class or interface in java.io">IOException</A></CODE></DL>
</DD>
</DL>
<HR>
<A NAME="fromJson(java.io.Reader)"><!-- --></A><H3>
fromJson</H3>
<PRE>
public final <A HREF="../../../com/google/gson/TypeAdapter.html" title="type parameter in TypeAdapter">T</A> <B>fromJson</B>(<A HREF="http://docs.oracle.com/javase/1.5.0/docs/api/java/io/Reader.html?is-external=true" title="class or interface in java.io">Reader</A> in)
throws <A HREF="http://docs.oracle.com/javase/1.5.0/docs/api/java/io/IOException.html?is-external=true" title="class or interface in java.io">IOException</A></PRE>
<DL>
<DD>Converts the JSON document in <code>in</code> to a Java object. Unlike Gson's
similar <A HREF="../../../com/google/gson/Gson.html#fromJson(java.io.Reader, java.lang.Class)"><CODE>fromJson</CODE></A> method, this
read is strict. Create a <A HREF="../../../com/google/gson/stream/JsonReader.html#setLenient(boolean)"><CODE>lenient</CODE></A>
<code>JsonReader</code> and call <A HREF="../../../com/google/gson/TypeAdapter.html#read(com.google.gson.stream.JsonReader)"><CODE>read(JsonReader)</CODE></A> for lenient reading.
<P>
<DD><DL>
<DT><B>Returns:</B><DD>the converted Java object. May be null.
<DT><B>Throws:</B>
<DD><CODE><A HREF="http://docs.oracle.com/javase/1.5.0/docs/api/java/io/IOException.html?is-external=true" title="class or interface in java.io">IOException</A></CODE><DT><B>Since:</B></DT>
<DD>2.2</DD>
</DL>
</DD>
</DL>
<HR>
<A NAME="fromJson(java.lang.String)"><!-- --></A><H3>
fromJson</H3>
<PRE>
public final <A HREF="../../../com/google/gson/TypeAdapter.html" title="type parameter in TypeAdapter">T</A> <B>fromJson</B>(<A HREF="http://docs.oracle.com/javase/1.5.0/docs/api/java/lang/String.html?is-external=true" title="class or interface in java.lang">String</A> json)
throws <A HREF="http://docs.oracle.com/javase/1.5.0/docs/api/java/io/IOException.html?is-external=true" title="class or interface in java.io">IOException</A></PRE>
<DL>
<DD>Converts the JSON document in <code>json</code> to a Java object. Unlike Gson's
similar <A HREF="../../../com/google/gson/Gson.html#fromJson(java.lang.String, java.lang.Class)"><CODE>fromJson</CODE></A> method, this read is
strict. Create a <A HREF="../../../com/google/gson/stream/JsonReader.html#setLenient(boolean)"><CODE>lenient</CODE></A> <code>JsonReader</code> and call <A HREF="../../../com/google/gson/TypeAdapter.html#read(com.google.gson.stream.JsonReader)"><CODE>read(JsonReader)</CODE></A> for lenient reading.
<P>
<DD><DL>
<DT><B>Returns:</B><DD>the converted Java object. May be null.
<DT><B>Throws:</B>
<DD><CODE><A HREF="http://docs.oracle.com/javase/1.5.0/docs/api/java/io/IOException.html?is-external=true" title="class or interface in java.io">IOException</A></CODE><DT><B>Since:</B></DT>
<DD>2.2</DD>
</DL>
</DD>
</DL>
<HR>
<A NAME="fromJsonTree(com.google.gson.JsonElement)"><!-- --></A><H3>
fromJsonTree</H3>
<PRE>
public final <A HREF="../../../com/google/gson/TypeAdapter.html" title="type parameter in TypeAdapter">T</A> <B>fromJsonTree</B>(<A HREF="../../../com/google/gson/JsonElement.html" title="class in com.google.gson">JsonElement</A> jsonTree)</PRE>
<DL>
<DD>Converts <code>jsonTree</code> to a Java object.
<P>
<DD><DL>
<DT><B>Parameters:</B><DD><CODE>jsonTree</CODE> - the Java object to convert. May be <A HREF="../../../com/google/gson/JsonNull.html" title="class in com.google.gson"><CODE>JsonNull</CODE></A>.<DT><B>Since:</B></DT>
<DD>2.2</DD>
</DL>
</DD>
</DL>
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