1 *java.lang.StringBuffer* *StringBuffer* A thread-safe, mutable sequence of chara
3 public final class StringBuffer
4 extends |java.lang.AbstractStringBuilder|
5 implements |java.io.Serializable|
6 |java.lang.CharSequence|
8 |java.lang.StringBuffer_Description|
9 |java.lang.StringBuffer_Fields|
10 |java.lang.StringBuffer_Constructors|
11 |java.lang.StringBuffer_Methods|
13 ================================================================================
15 *java.lang.StringBuffer_Constructors*
16 |java.lang.StringBuffer()|Constructs a string buffer with no characters in it a
17 |java.lang.StringBuffer(CharSequence)|Constructs a string buffer that contains
18 |java.lang.StringBuffer(int)|Constructs a string buffer with no characters in i
19 |java.lang.StringBuffer(String)|Constructs a string buffer initialized to the c
21 *java.lang.StringBuffer_Methods*
22 |java.lang.StringBuffer.append(boolean)|
23 |java.lang.StringBuffer.append(char)|
24 |java.lang.StringBuffer.append(char[])|
25 |java.lang.StringBuffer.append(char[],int,int)|
26 |java.lang.StringBuffer.append(CharSequence)|Appends the specified CharSequence
27 |java.lang.StringBuffer.append(CharSequence,int,int)|
28 |java.lang.StringBuffer.append(double)|
29 |java.lang.StringBuffer.append(float)|
30 |java.lang.StringBuffer.append(int)|
31 |java.lang.StringBuffer.append(long)|
32 |java.lang.StringBuffer.append(Object)|
33 |java.lang.StringBuffer.append(String)|
34 |java.lang.StringBuffer.append(StringBuffer)|Appends the specified StringBuffer
35 |java.lang.StringBuffer.appendCodePoint(int)|
36 |java.lang.StringBuffer.capacity()|
37 |java.lang.StringBuffer.charAt(int)|
38 |java.lang.StringBuffer.codePointAt(int)|
39 |java.lang.StringBuffer.codePointBefore(int)|
40 |java.lang.StringBuffer.codePointCount(int,int)|
41 |java.lang.StringBuffer.delete(int,int)|
42 |java.lang.StringBuffer.deleteCharAt(int)|
43 |java.lang.StringBuffer.ensureCapacity(int)|
44 |java.lang.StringBuffer.getChars(int,int,char[],int)|
45 |java.lang.StringBuffer.indexOf(String)|
46 |java.lang.StringBuffer.indexOf(String,int)|
47 |java.lang.StringBuffer.insert(int,boolean)|
48 |java.lang.StringBuffer.insert(int,char)|
49 |java.lang.StringBuffer.insert(int,char[])|
50 |java.lang.StringBuffer.insert(int,char[],int,int)|
51 |java.lang.StringBuffer.insert(int,CharSequence)|
52 |java.lang.StringBuffer.insert(int,CharSequence,int,int)|
53 |java.lang.StringBuffer.insert(int,double)|
54 |java.lang.StringBuffer.insert(int,float)|
55 |java.lang.StringBuffer.insert(int,int)|
56 |java.lang.StringBuffer.insert(int,long)|
57 |java.lang.StringBuffer.insert(int,Object)|
58 |java.lang.StringBuffer.insert(int,String)|
59 |java.lang.StringBuffer.lastIndexOf(String)|
60 |java.lang.StringBuffer.lastIndexOf(String,int)|
61 |java.lang.StringBuffer.length()|
62 |java.lang.StringBuffer.offsetByCodePoints(int,int)|
63 |java.lang.StringBuffer.replace(int,int,String)|
64 |java.lang.StringBuffer.reverse()|
65 |java.lang.StringBuffer.setCharAt(int,char)|
66 |java.lang.StringBuffer.setLength(int)|
67 |java.lang.StringBuffer.subSequence(int,int)|
68 |java.lang.StringBuffer.substring(int)|
69 |java.lang.StringBuffer.substring(int,int)|
70 |java.lang.StringBuffer.toString()|
71 |java.lang.StringBuffer.trimToSize()|
73 *java.lang.StringBuffer_Description*
75 A thread-safe, mutable sequence of characters. A string buffer is like a
76 (|java.lang.String|) , but can be modified. At any point in time it contains
77 some particular sequence of characters, but the length and content of the
78 sequence can be changed through certain method calls.
80 String buffers are safe for use by multiple threads. The methods are
81 synchronized where necessary so that all the operations on any particular
82 instance behave as if they occur in some serial order that is consistent with
83 the order of the method calls made by each of the individual threads involved.
85 The principal operations on a StringBuffer are the append and insert methods,
86 which are overloaded so as to accept data of any type. Each effectively
87 converts a given datum to a string and then appends or inserts the characters
88 of that string to the string buffer. The append method always adds these
89 characters at the end of the buffer; the insert method adds the characters at a
92 For example, if z refers to a string buffer object whose current contents are
93 "start", then the method call z.append("le") would cause the string buffer to
94 contain "startle", whereas z.insert(4, "le") would alter the string buffer to
97 In general, if sb refers to an instance of a StringBuffer, then sb.append(x)
98 has the same effect as sb.insert(sb.length(),x).
100 Whenever an operation occurs involving a source sequence (such as appending or
101 inserting from a source sequence) this class synchronizes only on the string
102 buffer performing the operation, not on the source.
104 Every string buffer has a capacity. As long as the length of the character
105 sequence contained in the string buffer does not exceed the capacity, it is not
106 necessary to allocate a new internal buffer array. If the internal buffer
107 overflows, it is automatically made larger.
109 As of release JDK 5, this class has been supplemented with an equivalent class
110 designed for use by a single thread, (|java.lang.StringBuilder|) . The
111 StringBuilder class should generally be used in preference to this one, as it
112 supports all of the same operations but it is faster, as it performs no
116 *java.lang.StringBuffer()*
118 public StringBuffer()
120 Constructs a string buffer with no characters in it and an initial capacity of
124 *java.lang.StringBuffer(CharSequence)*
126 public StringBuffer(java.lang.CharSequence seq)
128 Constructs a string buffer that contains the same characters as the specified
129 CharSequence. The initial capacity of the string buffer is 16 plus the length
130 of the CharSequence argument.
132 If the length of the specified CharSequence is less than or equal to zero, then
133 an empty buffer of capacity 16 is returned.
135 seq - the sequence to copy.
137 *java.lang.StringBuffer(int)*
139 public StringBuffer(int capacity)
141 Constructs a string buffer with no characters in it and the specified initial
144 capacity - the initial capacity.
146 *java.lang.StringBuffer(String)*
148 public StringBuffer(java.lang.String str)
150 Constructs a string buffer initialized to the contents of the specified string.
151 The initial capacity of the string buffer is 16 plus the length of the string
154 str - the initial contents of the buffer.
156 *java.lang.StringBuffer.append(boolean)*
158 public synchronized |java.lang.StringBuffer| append(boolean b)
163 *java.lang.StringBuffer.append(char)*
165 public synchronized |java.lang.StringBuffer| append(char c)
170 *java.lang.StringBuffer.append(char[])*
172 public synchronized |java.lang.StringBuffer| append(char[] str)
177 *java.lang.StringBuffer.append(char[],int,int)*
179 public synchronized |java.lang.StringBuffer| append(
187 *java.lang.StringBuffer.append(CharSequence)*
189 public |java.lang.StringBuffer| append(java.lang.CharSequence s)
191 Appends the specified CharSequence to this sequence.
193 The characters of the CharSequence argument are appended, in order, increasing
194 the length of this sequence by the length of the argument.
196 The result of this method is exactly the same as if it were an invocation of
197 this.append(s, 0, s.length());
199 This method synchronizes on this (the destination) object but does not
200 synchronize on the source (s).
202 If s is null, then the four characters "null" are appended.
204 s - the CharSequence to append.
206 Returns: a reference to this object.
207 *java.lang.StringBuffer.append(CharSequence,int,int)*
209 public synchronized |java.lang.StringBuffer| append(
210 java.lang.CharSequence s,
217 *java.lang.StringBuffer.append(double)*
219 public synchronized |java.lang.StringBuffer| append(double d)
224 *java.lang.StringBuffer.append(float)*
226 public synchronized |java.lang.StringBuffer| append(float f)
231 *java.lang.StringBuffer.append(int)*
233 public synchronized |java.lang.StringBuffer| append(int i)
238 *java.lang.StringBuffer.append(long)*
240 public synchronized |java.lang.StringBuffer| append(long lng)
245 *java.lang.StringBuffer.append(Object)*
247 public synchronized |java.lang.StringBuffer| append(java.lang.Object obj)
252 *java.lang.StringBuffer.append(String)*
254 public synchronized |java.lang.StringBuffer| append(java.lang.String str)
259 *java.lang.StringBuffer.append(StringBuffer)*
261 public synchronized |java.lang.StringBuffer| append(java.lang.StringBuffer sb)
263 Appends the specified StringBuffer to this sequence.
265 The characters of the StringBuffer argument are appended, in order, to the
266 contents of this StringBuffer, increasing the length of this StringBuffer by
267 the length of the argument. If sb is null, then the four characters "null" are
268 appended to this StringBuffer.
270 Let n be the length of the old character sequence, the one contained in the
271 StringBuffer just prior to execution of the append method. Then the character
272 at index k in the new character sequence is equal to the character at index k
273 in the old character sequence, if k is less than n; otherwise, it is equal to
274 the character at index k-n in the argument sb.
276 This method synchronizes on this (the destination) object but does not
277 synchronize on the source (sb).
279 sb - the StringBuffer to append.
281 Returns: a reference to this object.
282 *java.lang.StringBuffer.appendCodePoint(int)*
284 public synchronized |java.lang.StringBuffer| appendCodePoint(int codePoint)
289 *java.lang.StringBuffer.capacity()*
291 public synchronized int capacity()
296 *java.lang.StringBuffer.charAt(int)*
298 public synchronized char charAt(int index)
303 *java.lang.StringBuffer.codePointAt(int)*
305 public synchronized int codePointAt(int index)
310 *java.lang.StringBuffer.codePointBefore(int)*
312 public synchronized int codePointBefore(int index)
317 *java.lang.StringBuffer.codePointCount(int,int)*
319 public synchronized int codePointCount(
326 *java.lang.StringBuffer.delete(int,int)*
328 public synchronized |java.lang.StringBuffer| delete(
335 *java.lang.StringBuffer.deleteCharAt(int)*
337 public synchronized |java.lang.StringBuffer| deleteCharAt(int index)
342 *java.lang.StringBuffer.ensureCapacity(int)*
344 public synchronized void ensureCapacity(int minimumCapacity)
349 *java.lang.StringBuffer.getChars(int,int,char[],int)*
351 public synchronized void getChars(
360 *java.lang.StringBuffer.indexOf(String)*
362 public int indexOf(java.lang.String str)
367 *java.lang.StringBuffer.indexOf(String,int)*
369 public synchronized int indexOf(
370 java.lang.String str,
376 *java.lang.StringBuffer.insert(int,boolean)*
378 public |java.lang.StringBuffer| insert(
385 *java.lang.StringBuffer.insert(int,char)*
387 public synchronized |java.lang.StringBuffer| insert(
394 *java.lang.StringBuffer.insert(int,char[])*
396 public synchronized |java.lang.StringBuffer| insert(
403 *java.lang.StringBuffer.insert(int,char[],int,int)*
405 public synchronized |java.lang.StringBuffer| insert(
414 *java.lang.StringBuffer.insert(int,CharSequence)*
416 public |java.lang.StringBuffer| insert(
418 java.lang.CharSequence s)
423 *java.lang.StringBuffer.insert(int,CharSequence,int,int)*
425 public synchronized |java.lang.StringBuffer| insert(
427 java.lang.CharSequence s,
434 *java.lang.StringBuffer.insert(int,double)*
436 public |java.lang.StringBuffer| insert(
443 *java.lang.StringBuffer.insert(int,float)*
445 public |java.lang.StringBuffer| insert(
452 *java.lang.StringBuffer.insert(int,int)*
454 public |java.lang.StringBuffer| insert(
461 *java.lang.StringBuffer.insert(int,long)*
463 public |java.lang.StringBuffer| insert(
470 *java.lang.StringBuffer.insert(int,Object)*
472 public synchronized |java.lang.StringBuffer| insert(
474 java.lang.Object obj)
479 *java.lang.StringBuffer.insert(int,String)*
481 public synchronized |java.lang.StringBuffer| insert(
483 java.lang.String str)
488 *java.lang.StringBuffer.lastIndexOf(String)*
490 public int lastIndexOf(java.lang.String str)
495 *java.lang.StringBuffer.lastIndexOf(String,int)*
497 public synchronized int lastIndexOf(
498 java.lang.String str,
504 *java.lang.StringBuffer.length()*
506 public synchronized int length()
511 *java.lang.StringBuffer.offsetByCodePoints(int,int)*
513 public synchronized int offsetByCodePoints(
520 *java.lang.StringBuffer.replace(int,int,String)*
522 public synchronized |java.lang.StringBuffer| replace(
525 java.lang.String str)
530 *java.lang.StringBuffer.reverse()*
532 public synchronized |java.lang.StringBuffer| reverse()
537 *java.lang.StringBuffer.setCharAt(int,char)*
539 public synchronized void setCharAt(
546 *java.lang.StringBuffer.setLength(int)*
548 public synchronized void setLength(int newLength)
553 *java.lang.StringBuffer.subSequence(int,int)*
555 public synchronized |java.lang.CharSequence| subSequence(
562 *java.lang.StringBuffer.substring(int)*
564 public synchronized |java.lang.String| substring(int start)
569 *java.lang.StringBuffer.substring(int,int)*
571 public synchronized |java.lang.String| substring(
578 *java.lang.StringBuffer.toString()*
580 public synchronized |java.lang.String| toString()
585 *java.lang.StringBuffer.trimToSize()*
587 public synchronized void trimToSize()