1 package org.davidmoten.rx.jdbc;
2
3 import java.util.ArrayList;
4 import java.util.Arrays;
5 import java.util.Collections;
6 import java.util.List;
7
8 import javax.annotation.Nonnull;
9
10 import com.github.davidmoten.guavamini.Preconditions;
11
12 import io.reactivex.Flowable;
13
14 abstract class ParametersBuilder<T> {
15
16 private static final Flowable<List<Object>> SINGLE_EMPTY_LIST = Flowable.just(Collections.emptyList());
17
18 private final List<Flowable<List<Object>>> parameterGroups = new ArrayList<>();
19
20 private final List<Object> parameterBuffer = new ArrayList<>();
21 private final SqlInfo sqlInfo;
22
23 ParametersBuilder(@Nonnull String sql) {
24 this.sqlInfo = SqlInfo.parse(sql);
25 }
26
27 @SuppressWarnings("unchecked")
28 public final T parameterStream(@Nonnull Flowable<?> values) {
29 Preconditions.checkNotNull(values);
30 if (sqlInfo.numParameters() == 0) {
31 parameterListStream(values.map(x -> Collections.emptyList()));
32 } else {
33 parameterListStream((Flowable<List<?>>) (Flowable<?>) values.buffer(sqlInfo.numParameters()));
34 }
35 return (T) this;
36 }
37
38 @SuppressWarnings("unchecked")
39 public final T parameterListStream(@Nonnull Flowable<List<?>> valueLists) {
40 Preconditions.checkNotNull(valueLists, "valueLists cannot be null");
41 useAndCloseParameterBuffer();
42 parameterGroups.add((Flowable<List<Object>>) (Flowable<?>) valueLists);
43 return (T) this;
44 }
45
46 public final T parameters(@Nonnull List<?> values) {
47 return parameterList(values.toArray());
48 }
49
50 @SuppressWarnings("unchecked")
51 public final T parameter(@Nonnull String name, Object value) {
52 Preconditions.checkNotNull(name, "name cannot be null");
53 parameterBuffer.add(new Parameter(name, value));
54 return (T) this;
55 }
56
57 public final T parameter(Object value) {
58 return parameters(value);
59 }
60
61 public final T parameters(@Nonnull Object... values) {
62 return parameterList(values);
63 }
64
65 @SuppressWarnings("unchecked")
66 private final T parameterList(Object[] values) {
67 Preconditions.checkNotNull(values);
68 if (values.length == 0) {
69
70 return (T) this;
71 }
72 Preconditions.checkArgument(sqlInfo.numParameters() == 0 || values.length % sqlInfo.numParameters() == 0,
73 "number of values should be a multiple of number of parameters in sql: " + sqlInfo.sql());
74 Preconditions.checkArgument(Arrays.stream(values)
75 .allMatch(o -> sqlInfo.names().isEmpty() || (o instanceof Parameter && ((Parameter) o).hasName())));
76 for (Object val : values) {
77 if (val == null) {
78 parameterBuffer.add(Parameter.NULL);
79 } else {
80 parameterBuffer.add(val);
81 }
82 }
83 return (T) this;
84 }
85
86 final Flowable<List<Object>> parameterGroupsToFlowable() {
87 useAndCloseParameterBuffer();
88 Flowable<List<Object>> pg;
89 if (parameterGroups.isEmpty()) {
90 pg = SINGLE_EMPTY_LIST;
91 } else {
92 pg = Flowable.concat(parameterGroups);
93 }
94 return pg;
95 }
96
97 private void useAndCloseParameterBuffer() {
98
99 if (!parameterBuffer.isEmpty()) {
100 Flowable<List<Object>> p;
101 if (sqlInfo.numParameters() > 0) {
102 p = Flowable
103 .fromIterable(new ArrayList<>(parameterBuffer))
104 .buffer(sqlInfo.numParameters());
105 } else {
106 p = Flowable
107 .fromIterable(new ArrayList<>(parameterBuffer))
108 .map(x -> Collections.emptyList());
109 }
110 parameterGroups.add(p);
111 parameterBuffer.clear();
112 }
113 }
114
115 }