1<!DOCTYPE HTML PUBLIC "-//W3C//DTD HTML 4.01 Transitional//EN" "http://www.w3.org/TR/html4/loose.dtd"> 2<!--NewPage--> 3<HTML> 4<HEAD> 5<!-- Generated by javadoc (build 1.6.0-google-internal) on Mon Jan 04 20:47:56 PST 2010 --> 6<TITLE> 7Objects (Guava Libraries 2010.01.04) 8</TITLE> 9 10<META NAME="date" CONTENT="2010-01-04"> 11 12<LINK REL ="stylesheet" TYPE="text/css" HREF="../../../../stylesheet.css" TITLE="Style"> 13 14<SCRIPT type="text/javascript"> 15function windowTitle() 16{ 17 if (location.href.indexOf('is-external=true') == -1) { 18 parent.document.title="Objects (Guava Libraries 2010.01.04)"; 19 } 20} 21</SCRIPT> 22<NOSCRIPT> 23</NOSCRIPT> 24 25</HEAD> 26 27<BODY BGCOLOR="white" onload="windowTitle();"> 28<HR> 29 30 31<!-- ========= START OF TOP NAVBAR ======= --> 32<A NAME="navbar_top"><!-- --></A> 33<A HREF="#skip-navbar_top" title="Skip navigation links"></A> 34<TABLE BORDER="0" WIDTH="100%" CELLPADDING="1" CELLSPACING="0" SUMMARY=""> 35<TR> 36<TD COLSPAN=2 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if(window==top) { 66 document.writeln('<A HREF="../../../../allclasses-noframe.html"><B>All Classes</B></A>'); 67 } 68 //--> 69</SCRIPT> 70<NOSCRIPT> 71 <A HREF="../../../../allclasses-noframe.html"><B>All Classes</B></A> 72</NOSCRIPT> 73 74 75</FONT></TD> 76</TR> 77<TR> 78<TD VALIGN="top" CLASS="NavBarCell3"><FONT SIZE="-2"> 79 SUMMARY: <A HREF="#nested_class_summary">NESTED</A> | FIELD | CONSTR | <A HREF="#method_summary">METHOD</A></FONT></TD> 80<TD VALIGN="top" CLASS="NavBarCell3"><FONT SIZE="-2"> 81DETAIL: FIELD | CONSTR | <A HREF="#method_detail">METHOD</A></FONT></TD> 82</TR> 83</TABLE> 84<A NAME="skip-navbar_top"></A> 85<!-- ========= END OF TOP NAVBAR ========= --> 86 87<HR> 88<!-- ======== START OF CLASS DATA ======== --> 89<H2> 90<FONT SIZE="-1"> 91com.google.common.base</FONT> 92<BR> 93Class Objects</H2> 94<PRE> 95<A HREF="http://java.sun.com/javase/6/docs/api/java/lang/Object.html?is-external=true" title="class or interface in java.lang">java.lang.Object</A> 96 <IMG SRC="../../../../resources/inherit.gif" ALT="extended by "><B>com.google.common.base.Objects</B> 97</PRE> 98<HR> 99<DL> 100<DT><PRE>public final class <B>Objects</B><DT>extends <A HREF="http://java.sun.com/javase/6/docs/api/java/lang/Object.html?is-external=true" title="class or interface in java.lang">Object</A></DL> 101</PRE> 102 103<P> 104Helper functions that can operate on any <code>Object</code>. 105<P> 106 107<P> 108<DL> 109<DT><B>Since:</B></DT> 110 <DD>2010.01.04 <b>stable</b> (imported from Google Collections Library)</DD> 111<DT><B>Author:</B></DT> 112 <DD>Laurence Gonsalves</DD> 113</DL> 114<HR> 115 116<P> 117<!-- ======== NESTED CLASS SUMMARY ======== --> 118 119<A NAME="nested_class_summary"><!-- --></A> 120<TABLE BORDER="1" WIDTH="100%" CELLPADDING="3" CELLSPACING="0" SUMMARY=""> 121<TR BGCOLOR="#CCCCFF" CLASS="TableHeadingColor"> 122<TH ALIGN="left" COLSPAN="2"><FONT SIZE="+2"> 123<B>Nested Class Summary</B></FONT></TH> 124</TR> 125<TR BGCOLOR="white" CLASS="TableRowColor"> 126<TD ALIGN="right" VALIGN="top" WIDTH="1%"><FONT SIZE="-1"> 127<CODE>static class</CODE></FONT></TD> 128<TD><CODE><B><A HREF="../../../../com/google/common/base/Objects.ToStringHelper.html" title="class in com.google.common.base">Objects.ToStringHelper</A></B></CODE> 129 130<BR> 131 Support class for <A HREF="../../../../com/google/common/base/Objects.html#toStringHelper(java.lang.Object)"><CODE>toStringHelper(java.lang.Object)</CODE></A>.</TD> 132</TR> 133</TABLE> 134 135<!-- ========== METHOD SUMMARY =========== --> 136 137<A NAME="method_summary"><!-- --></A> 138<TABLE BORDER="1" WIDTH="100%" CELLPADDING="3" CELLSPACING="0" SUMMARY=""> 139<TR BGCOLOR="#CCCCFF" CLASS="TableHeadingColor"> 140<TH ALIGN="left" COLSPAN="2"><FONT SIZE="+2"> 141<B>Method Summary</B></FONT></TH> 142</TR> 143<TR BGCOLOR="white" CLASS="TableRowColor"> 144<TD ALIGN="right" VALIGN="top" WIDTH="1%"><FONT SIZE="-1"> 145<CODE>static boolean</CODE></FONT></TD> 146<TD><CODE><B><A HREF="../../../../com/google/common/base/Objects.html#equal(java.lang.Object, java.lang.Object)">equal</A></B>(<A HREF="http://java.sun.com/javase/6/docs/api/java/lang/Object.html?is-external=true" title="class or interface in java.lang">Object</A> a, 147 <A HREF="http://java.sun.com/javase/6/docs/api/java/lang/Object.html?is-external=true" title="class or interface in java.lang">Object</A> b)</CODE> 148 149<BR> 150 Determines whether two possibly-null objects are equal.</TD> 151</TR> 152<TR BGCOLOR="white" CLASS="TableRowColor"> 153<TD ALIGN="right" VALIGN="top" WIDTH="1%"><FONT SIZE="-1"> 154<CODE>static int</CODE></FONT></TD> 155<TD><CODE><B><A HREF="../../../../com/google/common/base/Objects.html#hashCode(java.lang.Object...)">hashCode</A></B>(<A HREF="http://java.sun.com/javase/6/docs/api/java/lang/Object.html?is-external=true" title="class or interface in java.lang">Object</A>... objects)</CODE> 156 157<BR> 158 Generates a hash code for multiple values.</TD> 159</TR> 160<TR BGCOLOR="white" CLASS="TableRowColor"> 161<TD ALIGN="right" VALIGN="top" WIDTH="1%"><FONT SIZE="-1"> 162<CODE>static <A HREF="../../../../com/google/common/base/Objects.ToStringHelper.html" title="class in com.google.common.base">Objects.ToStringHelper</A></CODE></FONT></TD> 163<TD><CODE><B><A HREF="../../../../com/google/common/base/Objects.html#toStringHelper(java.lang.Object)">toStringHelper</A></B>(<A HREF="http://java.sun.com/javase/6/docs/api/java/lang/Object.html?is-external=true" title="class or interface in java.lang">Object</A> object)</CODE> 164 165<BR> 166 Creates an instance of <A HREF="../../../../com/google/common/base/Objects.ToStringHelper.html" title="class in com.google.common.base"><CODE>Objects.ToStringHelper</CODE></A>.</TD> 167</TR> 168</TABLE> 169 <A NAME="methods_inherited_from_class_java.lang.Object"><!-- --></A> 170<TABLE BORDER="1" WIDTH="100%" CELLPADDING="3" CELLSPACING="0" SUMMARY=""> 171<TR BGCOLOR="#EEEEFF" CLASS="TableSubHeadingColor"> 172<TH ALIGN="left"><B>Methods inherited from class java.lang.<A HREF="http://java.sun.com/javase/6/docs/api/java/lang/Object.html?is-external=true" title="class or interface in java.lang">Object</A></B></TH> 173</TR> 174<TR BGCOLOR="white" CLASS="TableRowColor"> 175<TD><CODE><A HREF="http://java.sun.com/javase/6/docs/api/java/lang/Object.html?is-external=true#clone()" title="class or interface in java.lang">clone</A>, <A HREF="http://java.sun.com/javase/6/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://java.sun.com/javase/6/docs/api/java/lang/Object.html?is-external=true#finalize()" title="class or interface in java.lang">finalize</A>, <A HREF="http://java.sun.com/javase/6/docs/api/java/lang/Object.html?is-external=true#getClass()" title="class or interface in java.lang">getClass</A>, <A HREF="http://java.sun.com/javase/6/docs/api/java/lang/Object.html?is-external=true#hashCode()" title="class or interface in java.lang">hashCode</A>, <A HREF="http://java.sun.com/javase/6/docs/api/java/lang/Object.html?is-external=true#notify()" title="class or interface in java.lang">notify</A>, <A HREF="http://java.sun.com/javase/6/docs/api/java/lang/Object.html?is-external=true#notifyAll()" title="class or interface in java.lang">notifyAll</A>, <A HREF="http://java.sun.com/javase/6/docs/api/java/lang/Object.html?is-external=true#toString()" title="class or interface in java.lang">toString</A>, <A HREF="http://java.sun.com/javase/6/docs/api/java/lang/Object.html?is-external=true#wait()" title="class or interface in java.lang">wait</A>, <A HREF="http://java.sun.com/javase/6/docs/api/java/lang/Object.html?is-external=true#wait(long)" title="class or interface in java.lang">wait</A>, <A HREF="http://java.sun.com/javase/6/docs/api/java/lang/Object.html?is-external=true#wait(long, int)" title="class or interface in java.lang">wait</A></CODE></TD> 176</TR> 177</TABLE> 178 179<P> 180 181<!-- ============ METHOD DETAIL ========== --> 182 183<A NAME="method_detail"><!-- --></A> 184<TABLE BORDER="1" WIDTH="100%" CELLPADDING="3" CELLSPACING="0" SUMMARY=""> 185<TR BGCOLOR="#CCCCFF" CLASS="TableHeadingColor"> 186<TH ALIGN="left" COLSPAN="1"><FONT SIZE="+2"> 187<B>Method Detail</B></FONT></TH> 188</TR> 189</TABLE> 190 191<A NAME="equal(java.lang.Object, java.lang.Object)"><!-- --></A><H3> 192equal</H3> 193<PRE> 194public static boolean <B>equal</B>(<FONT SIZE="-1"><A HREF="http://jsr-305.googlecode.com/svn/trunk/javadoc/javax/annotation/Nullable.html?is-external=true" title="class or interface in javax.annotation">@Nullable</A></FONT> 195 <A HREF="http://java.sun.com/javase/6/docs/api/java/lang/Object.html?is-external=true" title="class or interface in java.lang">Object</A> a, 196 <FONT SIZE="-1"><A HREF="http://jsr-305.googlecode.com/svn/trunk/javadoc/javax/annotation/Nullable.html?is-external=true" title="class or interface in javax.annotation">@Nullable</A></FONT> 197 <A HREF="http://java.sun.com/javase/6/docs/api/java/lang/Object.html?is-external=true" title="class or interface in java.lang">Object</A> b)</PRE> 198<DL> 199<DD>Determines whether two possibly-null objects are equal. Returns: 200 201 <ul> 202 <li><code>true</code> if <code>a</code> and <code>b</code> are both null. 203 <li><code>true</code> if <code>a</code> and <code>b</code> are both non-null and they are 204 equal according to <A HREF="http://java.sun.com/javase/6/docs/api/java/lang/Object.html?is-external=true#equals(java.lang.Object)" title="class or interface in java.lang"><CODE>Object.equals(Object)</CODE></A>. 205 <li><code>false</code> in all other situations. 206 </ul> 207 208 <p>This assumes that any non-null objects passed to this function conform 209 to the <code>equals()</code> contract. 210<P> 211<DD><DL> 212</DL> 213</DD> 214</DL> 215<HR> 216 217<A NAME="hashCode(java.lang.Object...)"><!-- --></A><H3> 218hashCode</H3> 219<PRE> 220public static int <B>hashCode</B>(<A HREF="http://java.sun.com/javase/6/docs/api/java/lang/Object.html?is-external=true" title="class or interface in java.lang">Object</A>... objects)</PRE> 221<DL> 222<DD>Generates a hash code for multiple values. The hash code is generated by 223 calling <A HREF="http://java.sun.com/javase/6/docs/api/java/util/Arrays.html?is-external=true#hashCode(java.lang.Object[])" title="class or interface in java.util"><CODE>Arrays.hashCode(Object[])</CODE></A>. 224 225 <p>This is useful for implementing <A HREF="http://java.sun.com/javase/6/docs/api/java/lang/Object.html?is-external=true#hashCode()" title="class or interface in java.lang"><CODE>Object.hashCode()</CODE></A>. For example, 226 in an object that has three properties, <code>x</code>, <code>y</code>, and 227 <code>z</code>, one could write: 228 <pre> 229 public int hashCode() { 230 return Objects.hashCode(getX(), getY(), getZ()); 231 }</pre> 232 233 <b>Warning</b>: When a single object is supplied, the returned hash code 234 does not equal the hash code of that object. 235<P> 236<DD><DL> 237</DL> 238</DD> 239</DL> 240<HR> 241 242<A NAME="toStringHelper(java.lang.Object)"><!-- --></A><H3> 243toStringHelper</H3> 244<PRE> 245public static <A HREF="../../../../com/google/common/base/Objects.ToStringHelper.html" title="class in com.google.common.base">Objects.ToStringHelper</A> <B>toStringHelper</B>(<A HREF="http://java.sun.com/javase/6/docs/api/java/lang/Object.html?is-external=true" title="class or interface in java.lang">Object</A> object)</PRE> 246<DL> 247<DD>Creates an instance of <A HREF="../../../../com/google/common/base/Objects.ToStringHelper.html" title="class in com.google.common.base"><CODE>Objects.ToStringHelper</CODE></A>. 248 249 <p>This is helpful for implementing <A HREF="http://java.sun.com/javase/6/docs/api/java/lang/Object.html?is-external=true#toString()" title="class or interface in java.lang"><CODE>Object.toString()</CODE></A>. For 250 example, in an object that contains two member variables, <code>x</code>, 251 and <code>y</code>, one could write:<pre> <tt> 252 public class ClassName { 253 public String toString() { 254 return Objects.toStringHelper(this) 255 .add("x", x) 256 .add("y", y) 257 .toString(); 258 } 259 }</tt> 260 </pre> 261 262 Assuming the values of <code>x</code> and <code>y</code> are 1 and 2, 263 this code snippet returns the string <tt>"ClassName{x=1, y=2}"</tt>. 264<P> 265<DD><DL> 266<DT><B>Since:</B></DT> 267 <DD>2010.01.04 <b>tentative</b></DD> 268</DL> 269</DD> 270</DL> 271<!-- ========= END OF CLASS DATA ========= --> 272<HR> 273 274 275<!-- ======= START OF BOTTOM NAVBAR ====== --> 276<A NAME="navbar_bottom"><!-- --></A> 277<A HREF="#skip-navbar_bottom" title="Skip navigation links"></A> 278<TABLE BORDER="0" WIDTH="100%" CELLPADDING="1" CELLSPACING="0" SUMMARY=""> 279<TR> 280<TD COLSPAN=2 BGCOLOR="#EEEEFF" CLASS="NavBarCell1"> 281<A NAME="navbar_bottom_firstrow"><!-- --></A> 282<TABLE BORDER="0" CELLPADDING="0" CELLSPACING="3" SUMMARY=""> 283 <TR ALIGN="center" VALIGN="top"> 284 <TD BGCOLOR="#EEEEFF" CLASS="NavBarCell1"> <A HREF="../../../../overview-summary.html"><FONT CLASS="NavBarFont1"><B>Overview</B></FONT></A> </TD> 285 <TD BGCOLOR="#EEEEFF" CLASS="NavBarCell1"> <A HREF="package-summary.html"><FONT CLASS="NavBarFont1"><B>Package</B></FONT></A> </TD> 286 <TD BGCOLOR="#FFFFFF" CLASS="NavBarCell1Rev"> <FONT CLASS="NavBarFont1Rev"><B>Class</B></FONT> </TD> 287 <TD BGCOLOR="#EEEEFF" CLASS="NavBarCell1"> <A HREF="class-use/Objects.html"><FONT CLASS="NavBarFont1"><B>Use</B></FONT></A> </TD> 288 <TD BGCOLOR="#EEEEFF" CLASS="NavBarCell1"> <A HREF="package-tree.html"><FONT CLASS="NavBarFont1"><B>Tree</B></FONT></A> </TD> 289 <TD BGCOLOR="#EEEEFF" CLASS="NavBarCell1"> <A HREF="../../../../deprecated-list.html"><FONT CLASS="NavBarFont1"><B>Deprecated</B></FONT></A> </TD> 290 <TD BGCOLOR="#EEEEFF" CLASS="NavBarCell1"> <A HREF="../../../../index-all.html"><FONT CLASS="NavBarFont1"><B>Index</B></FONT></A> </TD> 291 <TD BGCOLOR="#EEEEFF" CLASS="NavBarCell1"> <A HREF="../../../../help-doc.html"><FONT CLASS="NavBarFont1"><B>Help</B></FONT></A> </TD> 292 </TR> 293</TABLE> 294</TD> 295<TD ALIGN="right" VALIGN="top" ROWSPAN=3><EM> 296</EM> 297</TD> 298</TR> 299 300<TR> 301<TD BGCOLOR="white" CLASS="NavBarCell2"><FONT SIZE="-2"> 302 <A HREF="../../../../com/google/common/base/Joiner.MapJoiner.html" title="class in com.google.common.base"><B>PREV CLASS</B></A> 303 <A HREF="../../../../com/google/common/base/Objects.ToStringHelper.html" title="class in com.google.common.base"><B>NEXT CLASS</B></A></FONT></TD> 304<TD BGCOLOR="white" CLASS="NavBarCell2"><FONT SIZE="-2"> 305 <A HREF="../../../../index.html?com/google/common/base/Objects.html" target="_top"><B>FRAMES</B></A> 306 <A HREF="Objects.html" target="_top"><B>NO FRAMES</B></A> 307 <SCRIPT type="text/javascript"> 308 <!-- 309 if(window==top) { 310 document.writeln('<A HREF="../../../../allclasses-noframe.html"><B>All Classes</B></A>'); 311 } 312 //--> 313</SCRIPT> 314<NOSCRIPT> 315 <A HREF="../../../../allclasses-noframe.html"><B>All Classes</B></A> 316</NOSCRIPT> 317 318 319</FONT></TD> 320</TR> 321<TR> 322<TD VALIGN="top" CLASS="NavBarCell3"><FONT SIZE="-2"> 323 SUMMARY: <A HREF="#nested_class_summary">NESTED</A> | FIELD | CONSTR | <A HREF="#method_summary">METHOD</A></FONT></TD> 324<TD VALIGN="top" CLASS="NavBarCell3"><FONT SIZE="-2"> 325DETAIL: FIELD | CONSTR | <A HREF="#method_detail">METHOD</A></FONT></TD> 326</TR> 327</TABLE> 328<A NAME="skip-navbar_bottom"></A> 329<!-- ======== END OF BOTTOM NAVBAR ======= --> 330 331<HR> 332 333</BODY> 334</HTML> 335
