Inner classes and implementation of ArrayList - Data Structures and Problem Solving Using Java - page 583

82 /**
83 * Obtains a primitive array view of the collection.
84 * @return the primitive array view.
85 */
86 public Object [ ] toArray( )
87 {
88 Object [ ] copy = new Object[ size( ) ];
89 int i = 0;
90
91 for( AnyType val : this )
92 copy[ i++ ] = val;
93
94 return copy;
95 }
96
97 public <OtherType> OtherType [ ] toArray( OtherType [ ] arr )
98 {
99 int theSize = size( );
100
101 if( arr.length < theSize )
102 arr = ( OtherType [ ] ) java.lang.reflect.Array.newInstance(
103 arr.getClass( ).getComponentType( ), theSize );
104

else if( theSize < arr.length )

arr[ theSize ] = null;

105

106
107 Object [ ] copy = arr;

int i = 0; 108

109
110 for( AnyType val : this )
111 copy[ i++ ] = val;
112
113 return copy;
114 }
115
116 /**
117 * Return a string representation of this collection.
118 */
119 public String toString( )
120 {
121 StringBuilder result = new StringBuilder( "[ " );
122
123 for( AnyType obj : this )
124 result.append( obj + " " );
125
126 result.append( "]" );
127
128 return result.toString( );
129 }
130 }

figure 15.12
Sample implementation of AbstractCollection (part 3)