1 /*
2 * Copyright (c) 2004, Oracle and/or its affiliates. All rights reserved.
3 * DO NOT ALTER OR REMOVE COPYRIGHT NOTICES OR THIS FILE HEADER.
4 *
5 * This code is free software; you can redistribute it and/or modify it
6 * under the terms of the GNU General Public License version 2 only, as
7 * published by the Free Software Foundation. Oracle designates this
8 * particular file as subject to the "Classpath" exception as provided
9 * by Oracle in the LICENSE file that accompanied this code.
10 *
11 * This code is distributed in the hope that it will be useful, but WITHOUT
12 * ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or
13 * FITNESS FOR A PARTICULAR PURPOSE. See the GNU General Public License
14 * version 2 for more details (a copy is included in the LICENSE file that
15 * accompanied this code).
16 *
17 * You should have received a copy of the GNU General Public License version
18 * 2 along with this work; if not, write to the Free Software Foundation,
19 * Inc., 51 Franklin St, Fifth Floor, Boston, MA 02110-1301 USA.
20 *
21 * Please contact Oracle, 500 Oracle Parkway, Redwood Shores, CA 94065 USA
22 * or visit www.oracle.com if you need additional information or have any
23 * questions.
24 */
25
26 package sun.tools.jstat;
27
28 /**
29 * A class that represents a mathematical expression as a tree structure
30 * containing operators as interior nodes and operands as leaves. The
31 * operands can be literals or lazily bound variables.
32 *
33 * @author Brian Doherty
34 * @since 1.5
35 */
36 public class Expression {
37 private static int nextOrdinal;
38 private boolean debug = Boolean.getBoolean("Expression.debug");
39 private Expression left;
40 private Expression right;
41 private Operator operator;
42 private int ordinal = nextOrdinal++;
43
44 Expression() {
45 if (debug) {
46 System.out.println("Expression " + ordinal + " created");
47 }
48 }
49
50 void setLeft(Expression left) {
51 if (debug) {
52 System.out.println("Setting left on " + ordinal + " to " + left);
53 }
54 this.left = left;
55 }
56
57 Expression getLeft() {
58 return left;
59 }
60
61 void setRight(Expression right) {
62 if (debug) {
63 System.out.println("Setting right on " + ordinal + " to " + right);
64 }
65 this.right = right;
66 }
67
68 Expression getRight() {
69 return right;
70 }
71
72 void setOperator(Operator o) {
73 if (debug) {
74 System.out.println("Setting operator on " + ordinal + " to " + o);
75 }
76 this.operator = o;
77 }
78
79 Operator getOperator() {
80 return operator;
81 }
82
83 public String toString() {
84 StringBuilder b = new StringBuilder();
85 b.append('(');
86 if (left != null) {
87 b.append(left.toString());
88 }
89 if (operator != null) {
90 b.append(operator.toString());
91 if (right != null) {
92 b.append(right.toString());
93 }
94 }
95 b.append(')');
96 return b.toString();
97 }
98 }
|
1 /*
2 * Copyright (c) 2004, 2018, Oracle and/or its affiliates. All rights reserved.
3 * DO NOT ALTER OR REMOVE COPYRIGHT NOTICES OR THIS FILE HEADER.
4 *
5 * This code is free software; you can redistribute it and/or modify it
6 * under the terms of the GNU General Public License version 2 only, as
7 * published by the Free Software Foundation. Oracle designates this
8 * particular file as subject to the "Classpath" exception as provided
9 * by Oracle in the LICENSE file that accompanied this code.
10 *
11 * This code is distributed in the hope that it will be useful, but WITHOUT
12 * ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or
13 * FITNESS FOR A PARTICULAR PURPOSE. See the GNU General Public License
14 * version 2 for more details (a copy is included in the LICENSE file that
15 * accompanied this code).
16 *
17 * You should have received a copy of the GNU General Public License version
18 * 2 along with this work; if not, write to the Free Software Foundation,
19 * Inc., 51 Franklin St, Fifth Floor, Boston, MA 02110-1301 USA.
20 *
21 * Please contact Oracle, 500 Oracle Parkway, Redwood Shores, CA 94065 USA
22 * or visit www.oracle.com if you need additional information or have any
23 * questions.
24 */
25
26 package sun.tools.jstat;
27
28 import java.util.Optional;
29
30 /**
31 * A class that represents a mathematical expression as a tree structure
32 * containing operators as interior nodes and operands as leaves. The
33 * operands can be literals or lazily bound variables.
34 *
35 * @author Brian Doherty
36 * @since 1.5
37 */
38 public class Expression {
39 private static int nextOrdinal;
40 private boolean debug = Boolean.getBoolean("Expression.debug");
41 private Expression left;
42 private Expression right;
43 private Operator operator;
44 private int ordinal = nextOrdinal++;
45 private boolean required = false;
46
47 Expression() {
48 if (debug) {
49 System.out.println("Expression " + ordinal + " created");
50 }
51 }
52
53 void setLeft(Expression left) {
54 if (debug) {
55 System.out.println("Setting left on " + ordinal + " to " + left);
56 }
57 this.left = left;
58 this.left.setRequired(required);
59 }
60
61 Expression getLeft() {
62 return left;
63 }
64
65 void setRight(Expression right) {
66 if (debug) {
67 System.out.println("Setting right on " + ordinal + " to " + right);
68 }
69 this.right = right;
70 this.right.setRequired(required);
71 }
72
73 Expression getRight() {
74 return right;
75 }
76
77 void setOperator(Operator o) {
78 if (debug) {
79 System.out.println("Setting operator on " + ordinal + " to " + o);
80 }
81 this.operator = o;
82 }
83
84 Operator getOperator() {
85 return operator;
86 }
87
88 void setRequired(boolean req) {
89 this.required = req;
90 Optional.ofNullable(left).ifPresent(l -> l.setRequired(required));
91 Optional.ofNullable(right).ifPresent(r -> r.setRequired(required));
92 }
93
94 boolean isRequired() {
95 return required;
96 }
97
98 public String toString() {
99 StringBuilder b = new StringBuilder();
100 b.append('(');
101 if (left != null) {
102 b.append(left.toString());
103 }
104 if (operator != null) {
105 b.append(operator.toString());
106 if (right != null) {
107 b.append(right.toString());
108 }
109 }
110 b.append(')');
111 return b.toString();
112 }
113 }
|